Monthly Archives: July 2020

Personalised Approaches in Treating Early-Stage Hodgkin Lymphoma

Editorial

Early-stage Classical Hodgkin Lymphoma (HL) is now one of the most curable malignancies and one of the success stories of modern haemato-oncology. Great progress has been made since X-rays were used as one of the first examples of non-surgical cancer treatment in 1901 by Pusey.More than half a century later, the development of wide field megavoltage irradiation techniques to multiple lymph node chains led by Peters in the 1950’s and Kaplan in the 1960’s were transformational and meant for the first time there were long-term survivors treated for HL [1,2]. Increasing use of systemic chemotherapy in the 1970’s improved outcomes yet further. However, this improvement in tumour control came at a cost and follow-up in these long-term survivors led to the concerning observations that more patients were dying in later life from the consequences of their treatment than from recurrence of their HL [3,4].

In this century, the approach towards management of early-stage HL has therefore increasingly focused on improving the quality of long-term survival by aiming to decrease treatment‐induced mortality and morbidity whilst at the same time maintaining long-term disease control. The aims of treatment are to balance the best chance of cure against the risks of late side effects that may lead to reduced long-term survival and impaired quality of life. Striking the right balance in this treatment goal has in turn led to the ambition to develop a personalised approach to treating HL. However there remain many unmet challenges in achieving the goal of personalised therapy for HL and some of these will be outlined in this brief commentary. These challenges include moving beyond the well-established pre-treatment clinical risk stratification approaches, integrating [¹⁸F] fluorodeoxyglucose ([¹⁸F]FDG) Positron Emission Tomography (PET) response-adjusted therapy, integrating individual patient characteristics (age, sex, site of disease) alongside emerging biological biomarkers in the decision making.

Risk-adapted Strategies: Pre-treatment Clinical Risk Stratification and Combined Modality Therapy

Pre-treatment staging and clinical risk stratification have been important tools for treatment decision making in early-stage HL over recent decades.Most international groups have used clinical risk factors, such as number of involved nodal sites, Erythrocyte Sedimentation Rate (ESR), and the presence of mediastinal bulk or B-symptoms, to differentiate early-stage HL into favourable and unfavourable risk groups with different treatment approaches. A series of large randomised trials conducted by the German Hodgkin Study Group (GHSG) and European Organisation for the Research and Treatment of Cancer (EORTC) have used clinical risk stratification to optimise CMT approaches for early-stage HL [5-7] .The GHSG HD10 trial showed that 2 cycles of ABVD and 20Gy Involved Field Radiation Therapy (IFRT) delivered excellent long-term tumour control, with freedom from treatment failure of 91.1% at 5 years [8]. This CMT approach became widely established as a standard treatment approach in early-stage favourable HL.For early-stage unfavourable HL, the results from the GSHG HD11 using 4 x ABVD and 30 Gy IFRT provided 83% long-term Progression-Free Survival (PFS),with room for further clinical improvements [9]. In an attempt to improve outcomes further, the GHSG HD14 trial investigated intensification of chemotherapy with 2 cycles ofBEACOPP_escalated plus 2 x ABVD (2+2). This approached improved PFS in early-stage unfavourable HL, with an improved 5 year PFS difference of 6.2% over the “standard arm”. However, this “2 + 2” approach was associated with more acute haematological toxicity and no difference in long-term toxicity or overall survival, therefore this more intensified approach has not been widely adopted.

Whilst pre-treatment clinical risk stratification can be used to guide treatment selection within validated treatment protocols, there are a number of limitations. These include the fact that all adverse risk factors are given equal weight in scoring, albeit that mediastinal bulk appears to have influenced treatment decisions perhaps more than other risk factors [10].In view of these limitations, pre-clinical risk stratification is less frequently applied in many UK and US early-stage HL clinical trial protocols and patients with mediastinal bulk and B-symptoms are excluded from early stage protocols and treated as advanced-stage disease. Secondly, the prognostic value of pre-clinical risk stratification in the current era of PET- risk adapted therapy has become less clear. By way of example the in the UK NCRI PET adapted “RAPID” trial, the PET response after 3 cycles of ABVD was more important than preclinical risk factors with no difference in outcomes seen between patients who initially presented with favourable- and unfavourable-risk disease [11]. Importantly patients with mediastinal bulk and B-symptoms were excluded from this trial. Finally, risk stratification does not take account of other baseline variables that may have utility in early-stage HL, including Maximum Tumour Diameter (MTD) and metabolic tumour volume [12-14].

Emerging tissue and serum biomarkers may in future help to refine pre-treatment risk stratification and develop precision medicine strategies that reflect underlying disease biology [15]. Circulating biomarkers such as serum Thymus Activation-Related Cytokine (TARC) and circulating tumour DNA have prognostic value in HL but have not yet been evaluated within early-stage HL protocols [16,17]; further assessment and standardisation is required before wider clinical application.

Response-adapted Strategies: PET-directed Treatment

PET response assessment has emerged as one of the most powerful prognostic tools in HL over recent decades [18]. A number of large, randomised trials have informed the use of PET-adapted treatment approaches, including the UK NCRI RAPID trial, EORTC H10, US intergroup 50604 Phase II trial and GHSG HD16 trials [19-22]. The principal focus of these clinical trials has been to investigate the utility of PET as an imaging biomarker to deliver response-adjusted therapy with Chemotherapy Alone (CA) for those who achieve Complete Metabolic Response (CMR). In this way, the aim has been to potentially avoid RT and further reduce RT -related long-term toxicity. The first trial to report was the RAPID trial, which included 602 patients with stage I/IIA HL and no mediastinal bulk [22]. Patients received 3 cycles of ABVD followed by PET response assessment. Those achieving a CMR (defined as Deauville score 1-2) were randomly assigned to receive 30Gy IFRT or no further treatment. Approximately two-thirds of patients enrolled had a favourable risk profile according to GHSG or EORTC risk classification. PET-negative patients in the intent-to-treat and per-protocol cohorts had PFS differences of 3.8% (3-year PFS, 94.6% vs 90.8%) and 6.3% (3-year PFS, 97.1% vs 90.8%) favouring consolidative IFRT, respectively.

In a similar fashion, the EORTC/FondazioneItalianaLinfomi performed the HD10 trial in both Early stage Favourable (F) and unfavourable (U) patients. In the standard arm, all patients received either 3 (F) or 4 cycles (U) of ABVD followed by 30Gy ISRT. In the experimental arm, patients achieving CMR after 2 cycles ABVD received chemotherapy alone, with a total of 4 (F) or 6 (U) cycles of ABVD. In a pre-planned interim analysis of PET-negative patients, futility of the trial was declared by the independent data monitoring committee because of an increased number of HL-related events in the non-RT arms [23]. The 5-year PFS rates with and without RT were 99.0% and 87.1%, respectively for favourable-risk disease, and 92.1% and 89.6%, for unfavourable-risk disease. The GHSG HD16 trial compared 2 cycles of ABVD alone with 2 ABVD plus 20Gy IFRT in patients with favourable-risk early-stage HL that achieved CMR after chemotherapy [21]. Again, there was a PFS difference in favour of CMT, with 5-year PFS rates of 93.4% with CMT and 86.1% with ABVD.

Although non-inferiority of chemotherapy alone compared with CMT could not be demonstrated, it is important to note that overall survival rates were excellent, uniformly exceeding 95% for both CMT and chemotherapy alone at 5 years. In most studies, non-HL deaths were a greater risk and outnumbered HL-related deaths, irrespective of treatment approach [21,22]. Follow-up for these studies is still relatively short and it remains to be seen whether mortality from late RT-related toxicity has an impact on survival over the decades to come, therefore the optimum approach remains unclear.

To address whether intensified therapy can improve outcomes in early-stage HL, the H10 trial evaluated a response-adapted approach based on PET assessment after 2 cycles of ABVD.In the standard arm, PET-positive patients (Deauville score 3-5) continued with ABVD to receive a total of 4 (F) or 6 (U) cycles followed by 30Gy INRT, whilst in the experimental arm, PET-positive patients were switched to an intensified treatment with 2 x BEACOPP escalated plus 30 Gy INRT. Outcomes clearly favoured the experimental arm, with 5-year PFS rates of 90.6% compared with 77.4% for PET-positive patients in the standard arm and a trend towards improved overall survival (96.0% versus 89.3%, respectively, p=0.062) [19]. This approach has been adopted as standard of care in many centres, although the degree of PET-positivity is an important consideration. An analysis of PET-positive patients in the RAPID protocol has shown that patients with stage I/IIA non-bulky HL that achieve Deauville score 3 or 4 have excellent outcomes following 3 x ABVD and 30 Gy IFRT (5-year event-free survival rates 95.3% and 93.5%, respectively), thus may potentially be spared the additional toxicity of escalated BEACOPP, whilst those with Deauville score 5 have a much higher relapse risk [11].

Personalised Approaches to Treatment

PET-adapted trials provide important information regarding the risk of disease relapse with CMT and chemotherapy approaches, but consideration of the risks of early and late toxicity is equally as important in determining the optimum treatment approach. Radiation field, dose, sex, co-morbidities and age are all important considerations. A large study of HL survivors has shown secondary malignancy rates of up to 33% at 30 years, noting that many will have received more extended-field radiotherapy than is current practice. The standard incidence ratio of cancer was highest in those diagnosed aged 15-35 years, particularly with respect to breast cancer risk in females receiving mediastinal radiotherapy [24,25]. Similarly, in a study of teenage and young adult cancer survivors, the standardised mortality ratio for cardiac-related death was 3.8 for those diagnosed with HL, with the greatest relative and absolute increase in risk for those aged 15-19 years at diagnosis [26].

Given that the large RT fields and higher radiation doses (>40 Gy) of the past were largely implicated in the late side effects of the survivors, newer RT techniques, improvements in advanced RT delivery and substantial reductions in the RT field size and dose are now used. The International Lymphoma Radiation Oncology Group have led the current international standard of care, which is Involved Site Radiation Therapy (ISRT) [27]. ISRT represents a large normal tissue volume reduction from the previous wide RT treatment fields of the past [28,29], which is anticipated to reduce, but not eliminate, late toxicity.

These trials confirm that CMT provides the best disease control and help clinicians to quantify the risk of omitting RT when informing patients. Nevertheless, a PET-based approach using chemotherapy alone for those achieving CMR remains an entirely reasonable option for selected patients based on their individual characteristics or treatment goals. The decision about whether to omit RT after chemotherapy provides an insight into the challenges of modern effective cancer medicine, where life beyond cure is now a key consideration for most patients. Randomised trial results suggest that some patients can be safely treated with chemotherapy alone and these results inform the patient-specific discussion about the increased risk of relapse omitting RT. Examples where omitting RT may be the preferred option include a young woman with axillary or mediastinal disease where receiving RT to axillary and mediastinal lymph nodes may necessitate irradiating breast tissue and substantially increase the risk of breast cancer, or where cardiac structures may receive clinically significant RT doses in addition to the potential cardiac toxicity of anthracycline-based therapies. In these patients, the individual risk of relapse and the risk of RT-associated late effects including secondary cancer should be carefully considered. In many older or co-morbid patients, minimising acute chemotherapy toxicity may be more of a concern, and RT can be useful in reducing the risk of relapse and need for salvage therapies.

Of paramount importance indecision making in early stage HL is the patient’s informed choice as to whether a 3.6 to upto 12.1% reduction in the rate of relapse with the addition of RT is worth the potential risk of additional late toxicity, which often occurs decades after delivering the RT. Some patients will elect to receive RT because they do not want to live with the increased short term risk of relapse. Others will elect to minimise the long term risks of radiotherapy and accept an increased risk of local relapse, where late radiation toxicity, such as effects on the heart and the risk of a second cancer or breast cancer in younger women, are of greater concern [30]. Based on current evidence, CMT is preferred for patients at highest risk of relapse, or where the anticipated risk of late radiation toxicity is low or negligible. However, chemotherapy alone confers excellent overall survival rates and is a valid option for selected patients, particularly where the late toxicity risks of RT may be higher.

Can modelling help with this complex clinical risk decision making in evaluating the risks and benefits with these different treatment options and the important question of whether to consolidate with RT? Early attempts to do this have started [31], although this type of modelling is certainly not ready for routine clinical application at present. Whatever model is used can only be a reflection of the input data, for example, much of the long-term outcome data is derived from older studies using more extensive radiation fields [29]. Importantly, when complex clinical outcome scenarios are modelled, often using study-level rather than individual patient data, a multitude of underlying assumptions must be made.

In summary, considerable progress has been made in moving towards personalising treatment approaches in early-stage HL and in moving away from “one size fits all” with the same treatment approach for each clinical risk group. However, we currently have much more work to do before we are able implement this personalised approach for all patients.Currently discussing and agreeing the most appropriate treatment approach can be amongst the most difficult parts of decision making for the both haemato-oncologist, radiation oncologist and the patient.We are now making progress in moving from long established pre-treatment risk stratification dictating management approaches to integrate response-adapted approaches with PET alongside patient-specific characteristics of age, sex, site of disease and patient preferences. Only such a balanced, integrated and informed approach with long term detailed follow-up will lead to the personalised care required to further improve outcomes in early-stage HL.

References

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Lopinavir-ritonavir (LPV/r) for the Treatment of SARS-CoV-2 (COVID-19): A Systematic Review

Abstract

Background: SARS-CoV-2 is the pathogenic agent of COVID-19, which has affected more than 200 countries; infected over 4 million people and declared a global pandemic. At the time of writing, no approved definitive therapeutic treatment for COVID-19 is available. Many studies are still on-going. Lopinavir-ritonavir (LPV/r), or its combination has been advocated as a potential treatment. This study reviews the evidence of LPV/r usage in the treatment of SARS-CoV-2 infection.

Methods: A systematic review protocol was written based on the PRISMA Statement Article for review selected from electronic databases (PubMed, Embase and Medline). Inclusion criteria were: full English articles published between 2019 and 2020, accessible and peer-reviewed. The search keywords were: Lopinavir, COVID, and SARS-CoV-2. Studies fulfilling the inclusion criteria were included, regardless of study designs. Data were extracted from published reports.

Findings: As of 9 May 2020, 243 manuscripts were identified. Thirteen studies were included with a total of 494 patients. These consisted of clinical trials (n=2), case reports (n=5), case series (n=3), and retrospective cohort studies (n=3). In the thirteen studies, the use of LPV/r shortened the PCR negative-conversion time for SARS-CoV-2, the earliest as being 5 days (Range: 5 to 28 days), and clinical improvement was expected as early as 2 days (Range: 2 to 28 days).

Interpretation: Our review shows that the use of LPV/rmay be an effective treatment for non-severe COVID-19 patients, while only limited benefits were observed in severe COVID-19 patients.

Introduction

Coronavirus disease in 2019(COVID-19) is caused by SARS-CoV-2 infection, first reported from Wuhan, China in early December 2019 [1]. It spreads quickly with a reproductive number R0 between 2.2 [2] and 5.7 [3]. It has been declared a pandemic with over 200 countries affected [4]. More than 4 million patients have been infected, resulting in over 250,000 deaths (6.93% case-fatality rate) as of May 10, 2020 [5]. However, there is no definite effective treatment and vaccine against COVID-19. SARS-CoV-2 is a positive-sense single-stranded RNA virus with a diameter of 60-140nm [6]. It is a beta-coronavirus which includes MERS-CoV and SARS-CoV. It is believed to be zoonotic in origin, with close genetic linkage to bat coronavirus. The incubation period is 1-14 days, transmitted through droplets and close contacts [7]. Lopinavir and ritonavir (LPV/r) are protease inhibitors for treating HIV infection. Lopinavir is used in fix-dosage combination with ritonavir to increase bioavailability. LPV/r has been used in the treatment of SARS-CoV and MERS-CoV infection, with effective outcomes [8]. Preliminary research supported the use of LPV/r in COVID-19. It has been recommended by the Chinese Centre for Disease Control and Prevention(CDC) since their third amendment of guidelines [7]. Previously, an inconclusive rapid review was published [9]. Since then more studies have been performed on efficacy of LPV/r for COVID-19 from other Asian [10-14] and European countries [15]. This prompts a more comprehensive review. In this review, we included a summary review of thirteen studies on the usage of LPV/r for treatment of COVID-19, exploring its clinical efficacy, adverse events, and usage in special populations. The strengths and limitations of these studies will be discussed.

Methods

Search Strategy and Selection Criteria

The target reports of this review were peer-reviewed English articles that are accessible on the three electronic databases (PubMed, Embase, Medline). We limited the search period between 2019 and 2020. All patients included in the studies had COVID-19 infection confirmed by PCR testing. A systematic review protocol was written on the basis of PRISMA 2009 guidelines. The search keywords were lopinavir, COVID-19 and SARS-CoV-2. All existing literature with therapeutic data on the use of LPV/r for COVID-19 were included. Database outputs were combined to address the key issues:

1. The documentation of LPV/r for COVID-19 patients in clinical practice, regardless of patient characteristics, countries of residence, clinical settings and outcome measures.

2. Clinical outcomes of the treatment (recovery, mortality) and side effects, especially for special populations.

Study Selection and Validity Assessment

All papers fitting the inclusion criteria were selected and analysed. The inclusion criteria were:

1. Peer-reviewed English article with therapeutic data.

2. Accessible on the databases. (PubMed, Embase and Medline)

3. Published between 2019 and May 9 2020.

The titles, abstracts and full articles were independently screened by the authors. Following the PRISMA guidelines in PRISMA flow diagram, the study profile is shown in Figure 1. Duplicate articles were removed, and reasons for exclusions are documented in the table in Appendix. Quality assessments were assessed by CASP appraisal on each study (if appropriate). Bias or quality issues were minimized by cross-checking of quality assessments by the authors.

JPPR-3-2-312-g001

Figure 1. Study profile (PRISMA Flow Diagram).

Data Extraction and Bias Assessment

Data extraction was performed by Zhipeng Yan and Ching-Lung Lai with specific focus on: study design, population demographics, therapeutic outcomes, adverse events and other key findings (if appropriate). The principal source of potential bias was the lack of standardization of outcome measures: viral loads were measured after different days of treatment with LPV/r, usually without continuous monitoring. This review used a time-interval approach, with 5-days units, to assess the time for patients to become negative for PCR test for SARS-CoV-2. Patient recovery was classified into six different groups: 1-5 days, 6-10 days, 11-15 days, 16-20 days, 21-25 days and 26-30 days. Assessment was based on the reported data; without authors for extra or missing information.

Data Analysis

The following were analysed to assess the efficacy of LPV/r in COVID-19 patients: the time to obtain a negative-conversion of PCR test for SARS-CoV-2 and the number of adverse events affecting different systems. All analyses were conducted using Microsoft Excel 2013.

Results

As of 9 May, 2020, 243 articles were identified initially. Using the PRISMA guidelines, the reasons for inclusion and exclusion are presented in a PRISMA flow diagram (Figure 1).

Thirteen studies were finally included (Table 1) :randomised clinical trial (n=2), case reports (n=5), retrospective cohort study (n=3), and case series (n=3). Ten out of the thirteen (76.9%) studies were conducted in China including Hong Kong, and one each from Italy, South Korea and Spain.A total of 494 patients were reported in the studies. The mean age was 52.8 years (excluding the seventh study in Table 1 because data on age were not complete). The outcome measures included time to clinical improvements, days to achieve negative-conversion in PCR detection for SARS-CoV-2 and mortality (Tables 1 and 2).

Table 1: Summary of the thirteen selected studies.
	Name of the study	Cityandcountry	Sample size	Age(mean)	Gender	Type of study	Therapeutic treatment	Type/Number of patients & %	Outcomes(recovery/mortality)	Quality assessment(applicable/inapplicable)
1	Cao, B., Wang, Y., Wen, D., et al. A Trial of Lopinavir-Ritonavir in Adults Hospitalized with Severe Covid-19. N Engl J Med 2020. May 7. DOI:10.1056/NEJMoa2001282	Wuhan,China	199	58 Y	120 M 79 F	Randomized controlled trial	LPV/r	LPV/r: 99 patients, (49.7%) Standard Care: 100 patients, (50.3%)	-No benefit was observed with LPV/r treatment beyond standard care in severe COVID-19 patients. -19 patients on intervention arm died. -3 premature deaths in LPV/r group within 24 hours after randomization	-A focused issue addressed. -Randomization performed with intention-to-treat analysis. -Population were properly accounted their inclusion -Not blinded. -Baseline demographics was similar in both groups. -Primary outcome clearly specified. -Showed little benefits without statistical significance. -Total 5 patients dropped out: 3 premature death, 2 failedprescriptions of LPV/r by physician.
2	Hung IFN LK, Tso EYK, et al. Triple combination of interferon beta-1b, lopinavir–ritonavir, and ribavirin in the treatment of patients admitted to hospital with COVID-19: an open-label, randomised, phase 2 trial. Lancet. 2020.May 8. DOI:10.1016/S0140-6736(20)31042-4	Hong Kong, China	127	52 Y	68 M 59 F	Randomised controlled trial	LPV/r + IFN-ß* + ribavirin	LPV/r + IFN-ß + ribavirin: 86 patients, (67.7%) LPV/r control group: 41 patients (32.2%)	-Triple therapy group had a significantly shorter median time for negative-conversion PCR test for SARS-CoV-2: Triple therapy group (7 days, [IQR 5-11]) vs. control group (12 days [IQR 8-15]); hazard ratio 4.37 [95% CI 1.86-10.24], p=0.0010 -Triple therapy group achieved a significantly shorter median time to National Early Warning Score 2 (NEWS2) of 0: Triple therapy group (4 days, [IQR 3-8]) vs. control group (8 days, [IQR 7-9]), p<0.0001. -Triple therapy achieved a significantly shorter median time to Sequential Organ Failure Assessment (SOFA) score to reach zero: Triple therapy group (3.0 days, [IQR 1.0-8.0]) vs. control group (8.0 days, [IQR 6.5-9.0]) -Shorter median duration of stay in triple therapy group: triple therapy group (9 days; [IQR 7-13]) vs. control group (14.5 days, [IQR 9.3-16.0]) -No patient died.	-A focused issue addressed. -Randomization performed. -Population were properly accounted their inclusion. -Not blinded. -Baseline demographics was similar in both groups. -Primary outcome clearly specified. -Secondary outcome clearly specified. -1 patient in control group dropped out due to biochemical hepatitis.
3	Righi, G., & Del Popolo, G. COVID-19 tsunami: the first case of a spinal cord injury patient in Italy. Spinal Cord Ser Cases 2020, 6: 22.	Firenze, Italy	1	56 Y	1 M	Case report	LPV/r, and HCQ†	LPV/r and HCQ: 1 patient (100%)	-Fever subsided 2 days after treated with LPV/r and HCQ. -Low-dose oxygen therapy was not required 3 days after treated with LPV/r and HCQ.	-Use of combination treatment that masked the real therapeutic outcome of LPV/r. -In contrast to the spinal cord injury-induced immune depression syndrome, the patient was discharged with complete healing within 2 weeks. -Reported that absence of cough as the presenting symptoms in spinal cord injury. -Only one case. -Side effects of medication not reported.
4	Lim, J., Jeon, S., Shin, H. Y., et al. Case of the Index Patient Who Caused Tertiary Transmission of COVID-19 Infection in Korea: the Application of Lopinavir/Ritonavir for the Treatment of COVID-19 Infected Pneumonia Monitored by Quantitative RT-PCR. J Korean Med Sci 2020, 35: e79.	Goyang, South Korea	1	54 Y	1 M	Case report	LPV/r	LPV/r: 1 patient (100%)	-Fever subsided 5 days after treatment with LPV/r. -Undetectable viral load since the second day after taking LPV/r.	-Difficult to determine whether recovery was due to natural cause or use of LPV/r, due to the late administration of drugs. -Only one case.
5	Fernandez-Ruiz, M., Andres, A., Loinaz, C., et al. COVID-19 in solid organ transplant recipients: a single-center case series from Spain. Am J Transplant 2020. Apr 16. DOI:10.1111/ajt.15929	Madrid, Spain	18	71 Y	14 M 4 F	Single centre retrospective case series	LPV/r HCQ IFN-ß IVIg‡ Tocilizumab No antivirals	LPV/r: 1/18 (5.56%) LPV/r + HCQ: 6/18 (33.3%) LPV/r + HCQ + IFN-ß: 2/18 (11.1%) HCQ: 5/18 (27.8%) HCQ + IVIg: 1/18 (5.56%) HCQ + IFN-ß: 1/18 (5.56%) no anti-viral: 2/18 (11.1%)	-A total of 5 deaths: 4 receiving LPV/r died, and 1 receiving standard care without anti-viral agent died. -For patients on HCQ, 2 showed clinical improvements, 1 showed mild ARDS, 1 showed persistent respiratory failure and 1 died. -For patients on LPV/r together with HCQ, 2 showed clinical improvement and discharged. The other 3 showed persistent respiratory failure, mild ARDS and death respectively. -The patient on HCQ and IVIg was discharged. -The patients on LPV/r, HCQ and IFN-ß were discharged home. -Patients received no antivirals resulted in 1 death and 1 low-grade fever till the end of study.	-Small sample size. -No numerical data provided to tell the efficacy of drugs by measurement of viral load change during the study. -Single centre. -Only 2 patients performed cytokine study. -Side effect of drugs not reported.
6	Tang, B., Li, S., Xiong, Y., et al. Coronavirus Disease 2019 (COVID-19) Pneumonia in a Hemodialysis Patient. Kidney Med 2020. Mar 12. DOI::10.1016/j.xkme.2020.03.001	Zhongshan, China	1	50 Y	1 M	Case report	LPV/r and moxifloxacin	LPV/r: 1 patient (100%)	-Nucleic acid test of SARS-CoV-2 turned negative in throat swab after 8 days of treatment. -No observable side effects of LPV/r.	-Only one case. -Use of moxifloxacin might masked the real therapeutic effect of LPV/r.
7	Ye, X. T., Luo, Y.L., Xia, S. C., et al. Clinical efficacy of lopinavir/ritonavir in the treatment of Coronavirus disease 2019. Eur Rev Med Pharmacol Sci 2020, 24, 3390-3396.	Rui’an, China	47	9 under 30 Y 38 over 30 Y	22 M 25 F	Single centre retrospective cohort study	LPV/r Adjuvant drugs§	LPV/r: 42/47 (89.4%) Adjuvant drugs: 5/47 (10.6%)	-Fever subsided earlier in test group. (test group 4.8±1.94 days vs control group 7.3±1.53 days, p=0.0364) -Shorter SARS-nCoV-2 RNA negative conversion time in test group. (test group 7.83.09 days vs control group 12.0±0.82 days, p=0.0219) -No observed liver toxicity.	-Single centre study. -Unbalanced treatment arm and control arm.
8	Wang, Z., Chen, X., Lu, Y., Chen, F., and Zhang, W. Clinical characteristics and therapeutic procedure for four cases with 2019 novel coronavirus pneumonia receiving combined Chinese and Western medicine treatment. Biosci Trends 2020, 14:64-68.	Shanghai, China	4	44.3 Y	3 M 1 F	Single centre retrospective observational case series	LPV/r Arbidol SFJDC¶	All received LPV/r, arbidol or SFJDC; or a combination of them. Detailed distribution was not provided.	-2 patients discharged with confirmed negative PCR on 2 consecutive throat swab 2019-nCoV test. -1 patient was negative on the first virus testing of 2019-nCoV. -All patients showed chest radiography improvement after 5-15 days of taking anti-viral agents. -Side effects of medication were not observed.	-Failed to mention exact regime for each patient. -Small sample size to assess the effect of combined Chinese and western medicine treatment for COVID-19.
9	Liu, F., Xu, A., Zhang, Y., et al. Patients of COVID-19 may benefit from sustained lopinavir-combined regimen and the increase of eosinophil may predict the outcome of COVID-19 progression. Int J Infect Dis 2020. Mar 12.DOI:10.1016/j.ijid.2020.03.013	Hangzhou China	10	42 Y	4 M 6 F	Single centre retrospective observational case series	LPV/r IFN-ß:	LPV/r + IFN-ß: 9/10 (90%) LPV/r: 1/10 (10%)	-The patient on LPV/r alone was discharged after 3 days of treatment. -3 patients on LPV/r + IFN-ß developed serious complications, persistent SARS-CoV-2 RNA PCR test positive and were transferred to more specialised unit, all presented with low eosinophil counts. -5 patients on “LPV/r + IFN-ß” developed severe O2 desaturation <93%. -No reported acute myocardial injury nor acute kidney injury.	-Small sample size in a single centre. -Failed to provide the treatment details and subsequent clinical progress of the 3 transferred patients.
10	Han, W., Quan, B., Guo, Y., et al.The course of clinical diagnosis and treatment of a case infected with coronavirus disease 2019. J Med Virol 2020, 92: 461-463.	Wuwei, China	1	47 Y	1 M	Case report	LPV/r Steroid IFN-α2b\|\| Ambroxol Moxifloxacin	LPV/r: 1 patient (100%)	-PCR tests for SARS-CoV-2 were persistently negative on day 6 and 7. -Discharged on day 10 with no reported complications during treatment period.	Failed to address whether the clinical improvement was due to LPV/r or other drugs.
11	Zhu, Z., Lu, Z., Xu, T., et al.Arbidol monotherapy is superior to lopinavir/ritonavir in treating COVID-19. J Infect 2020. Apr 10. DOI:10.1016/j.jinf.2020.03.060	Changzhou and Wuhu, China	50	36.0 Y	26 M 24 F	Retrospective cohort study	LPV/r Arbidol	LPV/r: 34/50 (68%) Arbidol: 16/50 (32%)	-None developed severe pneumonia or ARDS. -On day 7 after treatment, higher percentage of patients with undetectable viral load in Arbidol group (50%) vs. LPV/r group (23.5%). -On day 14 after treatment, all patients were with undetectable viral load in Arbidol group (100%) vs. LPV/r group (55.9%). -Patients with arbidol had a shorter duration of RNA positive period. (p<0.01)	Unbalanced treatment arm and control arm.
12	Deng, L., Li, C., Zeng, Q., et al.Arbidolcombined with LPV/rversus LPV/r aloneagainst Corona VirusDisease 2019: Aretrospective cohortstudy. J Infect 2020.Mar 11. DOI:10.1016/j.jinf.200.03.002	Zhuhai China	33	44.6 Y	17 M 16 F	Retrospective cohort study	LPV/r LPV/r + arbidol	LPV/r: 17/33 (51.5%) LPV/r + arbidol: 16/33 (48,.5%)	-On day 7, more patients were tested PCR negative for SARS-CoV-2 in respiratory sample in combination group [12/16 (75%) patients] than monotherapy group [6/17 (35%) patients]. -On day 14, more patients were tested PCR negative for SARS-CoV-2 in respiratory sample in combination group [15/16 (94%) patients] than monotherapy group [9/17 (53%) patients]	-Small sample size. -Non-randomized study. -Selection and unmeasured confounding bias.
13	Wang L, Xu X, Ruan J, Lin S, Jiang J, Ye H. Quadruple therapy for asymptomatic COVID- 19 infection patients. Expert Rev Anti Infect Ther. 2020. May 3. DOI:10.1080/14787210.2020.1758066	Fujian China	2	54.5 Y	1 M 1 F	Case report	LPV/r + arbidol + Lianhuaqingwen + IFN-α2b (quadruple therapy)	Quadruple therapy: 2 (100%)	-The Male and female patient had a negative PCR-test for SARS-CoV-2 after 7 days and 17 days respectively. -After receiving quadruple therapy, CT improvement was obtained after 10 days in male patient, and 8 days in female patient.	-Only two cases. -No control group to show the relative efficacy of quadruple therapy.

Abbreviation:
*IFN-ß: interferon-beta
†HCQ: hydroxychloroquine
‡IVIg: Intravenous Immunoglobulins
§ adjuvant drugs: interferon, arbidol, asmeton, eucalyptol limonene and penene entericsoft capsules and moxifloxacin.
¶SFJDC: Shufeng Jiedu Capsule
|| IFN-α2b: Interferon-alpha-2b.

Table2: Change of viral load, time to clinical improvement and reported side effects in thirteen studies.
Author	PCR finding of change of viral load after LPV/r-based treatment	Time to clinical improvement after LPV/r-based treatment	Adverse events (percentage of patients)
Cao et al. (2020) [20]	Percentage of patients with undetectable level SARS-CoV-2 by PCR in both arm was similar: (Treatment arm vs. control arm) Day 5: 34.5% vs. 32.9% Day 10: 50.0% vs. 48.6% Day 14: 55.2% vs. 57.1% Day 21: 58.6% vs. 58.6% Day 28: 60.3% vs. 58.6% p-value not reported.	1.No significant difference when assessed by improvement in National Early Warning Score 2 (NEWS2) in intention-to-treat analysis. 2.Slightly shorter median time to obtain clinical improvement in treatment arm. Treatment arm requires 15 days and standard care requires 16 days (hazard ratio, 1.39; 95% CI, 1.00 to 1.91). But this was without statistical significance.	Lymphopenia (8.0%) Respiratory failure (6.0%) Nausea (4.5%) Leukopenia (3.0%) Thrombocytopenia (3.0%) Abdominal discomfort (4.0%) Diarrhoea (2.0%) Stomach ache (2.0%) Neutropenia (2.0%) Increased total bilirubin (1.5%) Severe anaemia (1.5%) Acute kidney injury (1.5%) Increased creatinine (1.0%) Anaemia (1.0%) Rash (1.0%) Decreased appetite (1.0%) Shock (1.0%) Acute gastritis (1.0%) Haemorrhage of lower digestive tract (1.0%) Hypoalbuminemia (0.5%) Unconsciousness (0.5%) Prolonged QT interval (0.5%) Facial flushing (0.5%) Sleep disorders (0.5%) Secondary infection (0.5%) Disseminated intravascular coagulation (0.5%) Pneumothorax (0%) Sepsis (0%) Acute heart failure (0%)
Hung et al. (2020) [27]	Earlier PCR test negative-conversion for SARS-CoV-2 in triple therapy group in all specimens (nasopharyngeal swab, posterior oropharyngeal swab saliva, throat swab and stool): [Triple therapy group] Median time is 8 days, IQR: 6-12 days [Control group] Median time is 13 days, IQR: 8-15 days The reported p-value is 0.0010.	1.Earlier achievement of NEWS2 of 0 in triple therapy group (median is 4 days, IQR= 3 – 8 days) relative to control group (median is 8 days, IQR: 7 – 9 days). The p-value is <0.0001. 2.Earlier achievement of sequential organ failure assessment (SOFA) score of 0 in triple therapy group (median is 3.0 days; IQR:1.0-8.0 days) relative to control group (median is 8.0, IQR: 6.5 to 9.0 days). The p-value is 0.041.	Nausea (33.9%) Diarrhoea (40.9%) Rise of ALT (14.2%) Hyperbilirubinemia (5.51%) Sinus bradycardia (3.15%)
Righi et al. (2020) [15]	PCR nasopharyngeal swab turned negative on day 6 after treatment with LPV/r associated with hydroxychloroquine.	Fever ceased 2 days after LPV/r associated with hydroxychloroquine therapy.	No data.
Lim et al. (2020) [10]	PCR turned negative after 8 days treatment with LPV/r.	Fever ceased 6 days after treatment.	Psychiatric symptoms such as depression, insomnia, and suicidal thoughts (100%)
Fernandez-Ruiz et al. (2020) [26]	No numerical data.	6 patients were discharged between 8 to 23 days with adjustment of immunosuppressant dosage. 2 asymptomatic patients were on outpatient follow-up without any complication during treatment period.	No data.
Tang et al. (2020) [11]	PCR turned negative after 8 days treatment with LPV/r.	CT and laboratory test results showed improvements after 8 days of LPV/r.	Not observable.
Ye et al. (2020) [12]	PCR test turned negative in LPV/r group earlier. (test group: 7.8 ± 3.09 days vs. control group: 12.0 ± 0.82 days, p=0.0219)	1.Earlier return to normal body temperature in test group. (test group: 4.8 ± 1.94 days vs. control group: 7.3 ± 1.53 days, p=0.0364) 2.Lower abnormal proportion of White blood cells, lymphocytes, C-reactive protein (CRP) and platelets in test group. 3.Lymphocytes, haemoglobin, granulocytes and CRP gradually decreased throughout the tests.	Liver biochemistry derangement. First measurement of liver biochemistry after treatment: [Treatment group] Rise of ALT (9.5%) Rise of AST (19%) [Control group] Rise of ALT (25%) Rise of AST (25%) Conclusion:Liver biochemistry derangement was not associated with side effects of medications.
Wang et al. (2020) [13]	4 patients were reported, their time taken to turn PCRnegative were 9,7,12 days and unreported in the 4th patient who was severely ill.	1.Time taken to obtain CT improvement was 9 days, 9 days, 6 days and 11 days. 2.2 patients obtained improvement of arterial blood gas (ABG) parameter after 5 days and 11 days of treatment. 1 patient was with normal ABG throughout and the days taken for the 4th patient to obtain ABG improvement was unreported.	No data.
Liu et al. (2020) [14]	In the 7 discharged patients, viral load decreased continuously during day 3 to 14.Negative conversion of PCR was demonstrated 3 days after treatment in 1 patient, and 7-14 days in the remaining 6 patients. (Average=11.7 days, range=7-18 days) 3 remaining patients were with respiratory complications and transferred to other hospital. Their PCR remained positive before they were transferred, despite they were receiving LPV/r.	1.In the 7 discharged patients, radiograph improved continuously between day 6 and day 8. 2.Fever subsided after 4 days of treatment in the 7 discharged patients.	Hypokalaemia (70%) Digestive upsets (50%) Acute myocardial injury (0%) Acute kidney injury (0%)
Han et al. (2020) [57]	The patient obtained PCR test negative-conversion for SARS-CoV-2 on day 6 after treatment.	CT improvement shown since day 6 and discharged on day 7.	No data.
Zhu et al. (2020) [29]	On day 7, higher proportion of patients with undetectable viral load in arbidol group (50%) than LPV/r monotherapy group (23.5%). On day 14, higher proportion of patients with undetectable viral load in arbidol group (100%) than LPV/r monotherapy group (55.9%). Shorter duration of positive RNA test in arbidol group patients compared with LPV/r group (p<0.01).	Higher percentage of patients with fever subsided within 7 days in arbidol group (88.2%) vs. LPV/r monotherapy group (81.3%).	Rise of ALT (17.6%) Leukopenia (8.8%)
Deng et al. (2020) [25]	On day 7, higher proportion of patients obtained PCR test negative-conversion for SARS-CoV-2 in “LPV/r + Arbidol” combination group (75%) than LPV/r monotherapy group (35%), p<0.05. On day 14, higher proportion of patients obtained PCR test negative-conversion for SARS-CoV-2 in “LPV/r + Arbidol” combination group (94%) vs. LPV/r monotherapy group. (53%), p<0.05. Fewer patients showed PCR positive for stool SARS-CoV-2 in combination group (1 patient) vs. monotherapy group (3 patients).	On day 7, more patients gained CT improvement in combination group (69%) than monotherapy group (29%), p<0.05.	Elevated bilirubin (68.7%) Digestive upsets (43.7%) Depression (0%) Acute confusion (0%)
Wang et al. (2020) [58]	On day 7, the male patient obtained a negative conversion of PCR test for SARS-CoV-2. On day 17, the female patient obtained a negative conversion of PCR test for SARS-CoV-2.	1.Patients were asymptomatic throughout the treatment period. 2.The male patient showed CT improvement 10 days after treatment. 3.The female patient showed CT improvement 8 days after treatment.	Reported no adverse events

Studies with LPV/r in treatment regimen were classified as LPV/r-based treatment (N=364), whether as monotherapy or in combination with other agent(s). Non-LPV/r based treatment (N=130) included standard care only (N=99), hydroxychloroquine (N=9), arbidol (N=21). Standard care comprised of supplemental oxygen, non-invasive and invasive ventilation, antibiotics, vasopressor support, renal replacement therapy and extracorporeal membrane oxygenation (ECMO). Among the thirteen studies, four studies had non LPV/r-based treatment (Cao et al, Fernandez et al, Ye et al. and Zhu et al). Cao et al. included standard care only; Fernandez et al. included hydroxychloroquine, Ye et al. and Zhu et al. included arbidol.

Figure 2 shows the number of patients with PCR negative-conversion for SARS-CoV-2 at different time intervals.

JPPR-3-2-312-g002

Figure 2. Number of days after LPV/r-based treatment and number of patients with negative conversion of PCR test for SARS-CoV-2 in eleven studies.
*The study by Fernandez et al. is excluded: authors did not provide data on negative conversion of PCR test for SARS-CoV-2.
†The study by Hung et al. is excluded: the data were in median and inter-quartile range (IQR).

Figure 3 shows the number of adverse events in LPV/r-based treatment group and non-LPV/r based treatment group in the thirteen studies.

JPPR-3-2-312-g003

Figure 3. Total number of adverse events in different systems A) LPV/r-based treatment group reported in thirteen studies (N=364). B) non-LPV/r based treatment group in thirteen studies (N=130).

The distribution of adverse events in each system in respective treatment groups are as shown in Figures 4 and 5 respectively.

JPPR-3-2-312-g004

Figure 4. Distribution of adverse events in different systems in LPV/r-based treatment group in thirteen studies. (N=364).

JPPR-3-2-312-g005

Figure 5. bution of adverse events in different systems in non-LPV/r based treatment group in thirteen studies (N=130).

Discussion

This is the first comprehensive review on the use of LPV/r in COVID-19 patients. The 13 eligible articles include two randomised clinical trials; others were case reports, retrospective cohort studies or case series. LPV/r and its combination with other medications have been reported, including arbidol, interferons, ribavirin, hydroxychloroquine/chloroquine, intravenous immunoglobulins, antibiotics, corticosteroid and Chinese medicine. Quality assessment was applied to the thirteen articles. However, evidence was insufficient to conduct a meta-analysis. Most articles are of low quality; the study designs were not consistent. The studies also showed discordance in conclusions. In spite of these limitations, this review provides updated information on the therapeutic effects of LPV/r in COVID-19 patients.LPV/r had been regarded as the key therapeutic for treatment of COVID-19 patients. Its effectiveness was first proven in in vitro experiment, and included in the third amendment of the Chinese CDC treatment guidelines for severe novel coronavirus infection. De wildeet al. (2014) reported that with mean EC50 of lopinavirranging from 6.6 to 17.1 μM, lopinavir showed effective anti-viral outcome against SARS-CoV, MERS-CoV and hCoV-229E in vitro [16]. However, this was not observed with ritonavir. Previously Chu et al. (2004) reported that a lower rate of development into acute respiratory distress or death was observed in SARS patients receiving LPV/r, when compared with the control group treated with ribavirin and corticosteroids [17]. Since SARS-CoV-2, SARS-CoV and MERS-CoV are all beta-coronaviruses, it has been hypothesized that LPV/r may be effective to combat SARS-CoV-2.Choy et al. (2020) reported that lopinavir (EC50 at 26.1 μM) reduces viral RNA copy of SARS-CoV-2 in vitro, but not with ritonavir alone [18]. This is consistent with the finding of De wildeet al. (2014) on the effect of LPV/r on SARS-CoV. However, ritonavir is used with lopinavir in 1:4 ratio because it increases lopinavir bioavailability in vivo, as seen in HIV patients [19]. In the thirteen selected studies (Figure 2), most supported the use of LPV/r as a viable anti-viral agent for SARS-CoV-2. Patients were responsive to treatment with negative-conversions of PCR testing for SARS-CoV-2 after 5 to 28 days of treatment, and clinical improvement was observable as early as 2 days as reported by Lim et al. [10]. For those responsive to treatment, the majority of them had a SARS-CoV-2 negative-conversion time between 6 days to 10 days.

However, there are discordances concerning the efficacy of LPV/r for COVID-19. Liu et al. reported three severe patients receiving LPV/r who showed no obvious clinical improvement; their clinical conditions worsened and were transferred to specialised care hospital [14]. In the randomised, controlled, open-label trial involving 199 severe COVID-19 patients with median National Early Warning Score 2 (NEWS2) of 5 reported by Cao et al. , the intention-to-treat analysis showed median time to clinical improvement was only shortened by 1 day compared to the control group with standard care [20]. (hazard ratio, 1.39, 95% CI, 1.00 to 1.91). There was a better outcome of 28-day mortality (treatment group:19.2% vs standard care group: 25%; difference: -5.8%; 95% CI, -17.3 to 5.7), shorter median days of stay in Intensive Care Units (treatment group:6 days vs standard care group:11 days; difference: -5 days; 95% CI, -9 to 0) and higher percentage of patients with clinical improvement at day 14 (treatment group: 45.5% vs standard care group:30.0%; difference:15.5 percentage points; 95% CI, 2.2. to 28.8) [20]. But none of these reached statistical significance. It was concluded that LPV/r added to standard supportive care was not associated with clinical improvement or mortality in severe COVID-19 patients. However, Hung et al. showed that LPV/r-based triple therapy is effective in a study of 127 non-severe COVID-19 patients with median NEWS2 of 2, by shortening the PCR negative-conversion time to within a week in more than half of the patients.Most of the other studies with promising effects of LPV/r recruited patients with non-severe SARS-CoV-2 infection.

Severe COVID patients are defined with the following characteristics by the Chinese CDC in their Seventh Amendment of COVID-19 guideline [21]:

1. Dyspnea and tachypnea ≥ 30 breaths per minute

2. Blood oxygen saturation ≤ 93% when not in exertion

3. PaO₂/FiO₂ ≤ 300 mmHg.

4. Signs of respiratory failure, shock, multi-organ failure or need of mechanical ventilation and ICU admission.

In view of the insufficient clinical data to date, additional larger scale double-blinded randomized controlled trials, with classification of patient’s clinical status into severe and non-severe type, should be carried out before LPV/r can be adopted in international guidelines. Currently, it is advisable for physicians to classify the severity of COVID-19 patients. It is likely that LPV/r may be effective in reducing viral load in non-severe COVID-19 patients, but its benefits remain questionable in severe patients. Severe COVID-19 is associated with immunopathological damages such as diffuse alveolar damage with hyaline membrane formation [22]. This may be caused by cytokine storms or inflammatory processes [23]. Since 19% of patients have the severe form[24], patients should be classified soon after admission. Once recognised, they should be treated to minimize the cytokine storm. Steroid was used as adjuvant therapy in some studies [12,14,25-27]. This is debatable because Auyeunget al. (2005) showed that use of steroid was associated with adverse outcomes in SARS [28]. Combining LPV/r with other drugs seems to be an effective modality of treatment. Zhu et al. reported that arbidol monotherapy achieved better reduction of viral load to an undetectable level than LPV/r monotherapy on day 7 (arbidol: 50% vs LPV/r:23.5%) and on day 14 (arbidol:100% vs 54.9%) [29]. Deng et al. reported that an even higher proportion of negative-conversion of PCR test for SARS-CoV-2 could be achieved with “arbidol and LPV/r” combination therapy (Day 7: 75%, Day 14: 94%)than LPV/r monotherapy (Day 7:35%, Day 14: 53%) [25]. Hung et al. showed that an earlier PCR negative-conversion was also obtained in LPV/r-based triple therapy (median=8 days, IQR=6-12 days) than control group (median=13 days, IQR=8-15 days), p-value=0.0010. Combinations with remdesivir and hydroxychloroquine should also be studied together with LPV/r to explore the more effective combinations, they being inhibitors of SARS-CoV-2 through mediation of viral polymerase and the proofreading exoribonuclease [30,31]. Clinical usage of LPV/r requires extra care in special populations. Fernandez et al. reported 18 post-organ transplant patients on immunosuppressants. Therapeutic regimens and dosages were adjusted when LPV/r was initiated [26]. Calcineurin and mammalian target of rapamycin (mTOR) inhibitors were stopped, and prednisolone was reduced by 50% in these patients. The serum trough concentrations of LPV/r were obtained after 48-72 hours, with close monitoring for adjustment of dosage. The dosage of mycophenolate mofetil/mycophenolic acid (MMF/MPA) was decreased in patients receiving LPV/r. Similarly in the studies by Fan et al. and Zhang et al. on renal transplant recipients, patients were given reduced dosage of immunosuppressants and methylprednisolone [32,33]. When patients developed severe graft rejection, consideration of alternative antiviral and continuation of corticosteroid at reduced dose has been suggested [34]. Another group for special consideration are cancer patients due to drug interaction with CYP3A4, a common pathway for chemotherapeutic agents. Liang et al. showedthat cancer patients with COVID-19 were associated with higher risks of severe events compared to patients without cancers [35]. This might be due to the leukopenia and lymphopenia commonly found among COVID-19 patients [36], leading to a higher risk of super-infections. In addition, the dosage of some chemotherapeutic agents may require readjustment [37] such as docetaxel [38] anderlotinib [39]. Therefore, in managing drug interactions between chemotherapeutic and antiviral agents, it is advised to consider the following [35]:

1. Intentional postponing of adjuvant chemotherapy or elective surgery for stable cancer;

2. Strong personal protection provisions for cancer patients and survivors;

3. More intensive surveillance or treatment when cancer patients are infected with SARS-CoV-2, especially in older patients and those with comorbidities.

Another patient group with immunocompromised state are patients on hemodialysis. Hemodialysis predisposes to chronic immunocompromised state due to disorders of B cell and T cell function [40,41]. T cells play a vital role for patients’ recovery from other beta-coronavirus infection[42-44]. But lymphopeniais commonly observed in hemodialysis patients [45]. No dose adjustment is deemednecessary in the treatment of hemodialysis patients with COVID-19, probably due to the liver clearance and the high protein-binding capacity of LPV/r [26].The effects of COVID-19 on pregnancy are noteworthy. Li et al. summarized the outcomes of 55 pregnant COVID-19 women and 46 neonates: vertical transmission to neonates was not observed[46,47].This was further confirmed by Chen et al. [47]: 3 out of 4 infants tested negative for SARS-CoV-2 (consent was not obtained for the forth infant).Use of LPV/r in pregnancy is safe, as documented by a study of population-based surveillance in HIV-positive pregnancies. It found no increase in the risk of foetal anomalies, preterm birth nor low-birth weight infants [48]. This was further confirmed in pregnant mothers with COVID-19. However, it is advisable to have close surveillance of both the mothers and the neonates. In case of maternal hypoxia due to SARS-CoV-2 infection, there would be an increase of endothelin-1 and hypoxia-inducible factor, impairing placental perfusion to the fetus [49]. Therefore, at least one ultrasound after maternal recovery is recommended to monitor the potential intra-uterine growth retardation, which was observed in approximately 10% of COVID-19 pregnancies. However, SARS-CoV-2 infection during pregnancy was not found to be associated with an increased risk of spontaneous abortion and preterm birth [50]. Chen et al. did a study involving 118 pregnancy women and found that SARS-CoV-2 infection during pregnancy did not increase the risk of severe disease among pregnancy women. The risk is only half of that in the general population [51]. Pregnant women are at higher risks of hypercoagulability than the general population. Physicians should monitor possible thromboembolic events in severe COVID-19 pregnancy, because the incidence of venous thromboembolism is more than 30% in severe COVID-19 patients [52]. The side effects of LPV/r need to be monitored. These include nausea, vomiting, gastrointestinal disturbances, pancreatitis, hepatotoxicity, QT interval prolongation, PR interval prolongation, and metabolic disturbances [51]. In the 13 studies (Figures 3 and 4), of the 364 COVID-19 patients receiving LPV-r based treatment, 145 patients (39.8%) had gastrointestinal adverse effects after LPV/r treatment. Hepatic injury was observed in 56 patients (15.4%). 12 patients (3.30%) had respiratory failure. Prolongation of QT interval was only observed in 1 patient. Haematological alteration was observed in 39 patients (10.7%). Eight patients (2.20%) showed leukopenia. Granulocytes colony stimulating factor (GCSF)was prescribed whichprevented complications in 3 patients [29]. Other side effects such as metabolic disturbances and PR interval prolongation have not been reported. Because of the possible side effects, patients should be closely monitored. In digestive tract adverse effects, hydration status and electrolytes should be monitored. With severe nausea and vomiting, use of anti-emetics or stopping medication may be possible choices. However, the use of 5-HT3 receptor antagonists and neurokinin-1 receptor antagonists shall be cautious due to their risk of QT prolongation and prolonged serum concentration [53]. Liver biochemistry derangement may be due to the following causes: LPV/r induced, SARS-CoV-2 related or immune-mediated inflammation such as cytokine storm. Liver biochemistry usually returns to normal without specific treatment in mild COVID-19 [54]. Ye et al. reported liver enzyme elevations in both LPV/r-based and non LPV/r-based treatment groups, and it was found to be unrelated to treatment. However, with extensive hepatic damage orpre-existing liver diseases, close monitoring of liver biochemistry should be considered [55]. In immune-mediated inflammation, the use of glucocorticoid is unclear.

Prolonged QT interval and ventricular arrhythmia are two serious adverse effects of LPV/r.The Canadian Heart Rhythm Society has published guidelines on minimizing the risk [56]:

1. Discontinue unnecessary medications that prolong QT interval.

2. Identify low-risk outpatients who do not need further testing (no history of prolonged QT, unexplained syncope or family history of premature sudden cardiac death, no medications
which may prolong the QT interval, and/or prior known
normal QTc.

3. Performing baseline testing in hospitalized and high-risk patients. If the QTc is markedly prolonged, drugs which further prolong QTc should be avoided. Expert consultation may permit administration with mitigating precautions.

Conclusion

With the evidence to date, the review shows that LPV/r may be effective for treating non-severe COVID-19 patients, while only limited benefits are observed in severe COVID-19 patients. Clinical classification and close monitoring of drug dosage and treatment progress are recommended for special populations. Further research on LPV/r, precluding in combination with other drugs, are required to confirm its use for COVID-19 patients.

Evidence before This Study

Published studies on electronic databases such as Pubmed, Embase and Medline on the use of LPV/r in the treatment of COVID-19 patients are conflicting. Previously only an inconclusive rapid review was done. No systematic review nor meta-analysis have been performed to date to evaluate the results. The real therapeutic effect of LPV/r is debatable. A systematic search on the three electronic databases was done on 9 May, 2020 and outputs were gathered for a systematic review of the therapeutic outcome, adverse events and clinical management of special populations. Search terms used included: Lopinavir, SARS-CoV-2, COVID-19. Full peer-reviewed articles that are written in English, published between 2019 and 2020, accessible on the three databases are included in this systematic review.Items without therapeutic data were eliminated.

Added Value of This Study

The review selected thirteen articles with primary therapeutic data to look at the therapeutic effect of LPV/r, number of adverse events, distribution of adverse events in different systems and the precautions in prescribing LPV/r in special populations with COVID-19. Most studies were of low evidence value, with potential experimental bias. Their outcome measures varied. It is likely that LPV/r is effective in treating non-severe COVID-19 patients, but only limited benefits are observed in severe COVID-19 patients. Clinical classification of patients according to the severity of COVID-19 infections should be carried out for a better treatment plan.

Implications of All the Available Evidence

LPV/r may be considered in non-severe COVID-19 patients. Further research of LPV/r, preferably in combination with other antiviral agents, in severe COVID-19 patients is required for more effective treatment.

Contributions

Literature search was done by ZY, KLS and CLL. Searches screening, and article review was done by ZY, KLS and CLL. Study designs were done by ZY,KLS and CLL. Data extraction and analysis was done by ZY and CLL. Data interpretation was done by ZY and CLL. Manuscript writing was done by ZY, KLS and CLL.

Declaration of interests

Prof. Ching-Lung Lai has given sponsored lectures on hepatitis C for Abbvie Inc.

Ethical approval

No ethical approval is required since the whole review is based on published data on readily-accessible databases.

Acknowledgement

None.

Funding

None.

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Appendix

Appendix table. List of excluded papers
No.#	Authors	Title	Covid-19 Yes/No	Reason for exclusion
1	Khot WY, Nadkar MY. The 2019 Novel Coronavirus Outbreak – A Global Threat. J Assoc Physicians India. 2020;68:67-71.	The 2019 Novel Coronavirus Outbreak – A Global Threat	Yes	No details on LPV/r therapeutics
2	Ahmad A, Rehman MU, Alkharfy KM. An alternative approach to minimize the risk of coronavirus (Covid-19) and similar infections. Eur Rev Med Pharmacol Sci. 2020;24:4030-4.	An alternative approach to minimize the risk of coronavirus (Covid-19) and similar infections	Yes	No details on LPV/r therapeutics
3	Khan Z, Karatas Y, Rahman H. Anti COVID-19 Drugs: Need for More Clinical Evidence and Global Action. Adv Ther. 2020. Apr 29. DOI: 10.1007/s12325-020-01351-9	Anti COVID-19 Drugs: Need for More Clinical Evidence and Global Action	Yes	Review
4	Yousefifard M, Zali A, Mohamed Ali K, Madani Neishaboori A, Zarghi A, Hosseini M, et al. Antiviral therapy in management of COVID-19: a systematic review on current evidence. Arch Acad Emerg Med. 2020;8:e45.	Antiviral therapy in management of COVID-19: a systematic review on current evidence.	Yes	Review
5	Simsek Yavuz S, Unal S. Antiviral treatment of COVID-19. Turk J Med Sci. 2020;50:611-9.	Antiviral treatment of COVID-19	Yes	Review
6	Vanden Eynde JJ. COVID-19: A Brief Overview of the Discovery Clinical Trial. Pharmaceuticals (Basel, Switzerland) 2020 Apr 10. DOI: 10.3390/ph13040065	A Brief Overview of the Discovery Clinical Trial	Yes	Review
7	Liu YJ, Yang YL, Xu Y. [What we learned from SARS may provide important insights into understanding and management of coronavirus disease 2019]. Zhonghua Jie He He Hu Xi Za Zhi 2020 Apr 12;43:339-344.	[What we learned from SARS may provide important insights into understanding and management of coronavirus disease 2019]	Yes	Review
8	Rubin EJ, Baden LR, Morrissey S. Audio Interview: New Research on Possible Treatments for Covid-19. N Engl J Med. 2020;382:e30.	Audio Interview: New Research on Possible Treatments for Covid-19	Yes	Review
9	Lim J, Jeon S, Shin HY, Kim MJ, Seong YM, Lee WJ, et al. The Author’s Response: Case of the Index Patient Who Caused Tertiary Transmission of Coronavirus Disease 2019 in Korea: the Application of Lopinavir/Ritonavir for the Treatment of COVID-19 Pneumonia Monitored by Quantitative RT-PCR. J Korean Med Sci. 2020;35:e89.	Author’s Response: Case of the Index Patient Who Caused Tertiary Transmission of Coronavirus Disease 2019 in Korea: the Application of Lopinavir/Ritonavir for the Treatment of COVID-19 Pneumonia Monitored by Quantitative RT-PCR	Yes	No details on LPV/r therapeutics
10	Mothay D, Ramesh KV. Binding site analysis of potential protease inhibitors of COVID-19 using AutoDock. Virusdisease. 2020 2:1-6.	Binding site analysis of potential protease inhibitors of COVID-19 using AutoDock	Yes	No details on LPV/r therapeutics
11	McKee DL, Sternberg A, Stange U, Laufer S, Naujokat C. Candidate drugs against SARS-CoV-2 and COVID-19. Pharmacol Res. 2020:104859.	Candidate drugs against SARS-CoV-2 and COVID-19	Yes	Review
12	Inciardi RM, Lupi L, Zaccone G, Italia L, Raffo M, Tomasoni D, et al. Cardiac Involvement in a Patient With Coronavirus Disease 2019 (COVID-19). JAMA Cardiol. 2020. Mar 27. DOI: 10.1001/jamacardio.2020.1096	Cardiac Involvement in a Patient With Coronavirus Disease 2019 (COVID-19)	Yes	No details on LPV/r therapeutics
13	Naksuk N, Lazar S, Peeraphatdit TB. Cardiac safety of off-label COVID-19 drug therapy: a review and proposed monitoring protocol. Eur Heart J Acute Cardiovasc Care. 2020:2048872620922784.	Cardiac safety of off-label COVID-19 drug therapy: a review and proposed monitoring protocol	Yes	No details on LPV/r therapeutics
14	Kakodkar P, Kaka N, Baig MN. A Comprehensive Literature Review on the Clinical Presentation, and Management of the Pandemic Coronavirus Disease 2019 (COVID-19). Cureus 2020 Apr 06;12:1.	Comprehensive Literature Review on the Clinical Presentation, and Management of the Pandemic Coronavirus Disease 2019 (COVID-19)	Yes	Review
15	Qiu H, Wu J, Hong L, Luo Y, Song Q, Chen D. Clinical and epidemiological features of 36 children with coronavirus disease 2019 (COVID-19) in Zhejiang, China: an observational cohort study. Lancet Infect Dis. 2020. Mar 25. DOI: 10.1016/S1473-3099(20)30198-5	Clinical and epidemiological features of 36 children with coronavirus disease 2019 (COVID-19) in Zhejiang, China: an observational cohort study	Yes	No details on LPV/r therapeutics
16	Allameh S.F. All about COVID-19 in brief. New Microbes and New Infections. 2020;35:no pagination.	All about COVID-19 in brief	Yes	No details on LPV/r therapeutics
17	Du B, Qiu HB, Zhan X, Wang YS, Kang HYJ, Li XY, et al. [Pharmacotherapeutics for the new coronavirus pneumonia]. Zhonghua Jie He He Hu Xi Za Zhi 2020 Mar 12;43:173-176.	[Pharmacotherapeutics for the new coronavirus pneumonia]	Yes	Review
18	Liu K, Chen Y, Lin R, Han K. Clinical features of COVID-19 in elderly patients: A comparison with young and middle-aged patients. J Infect. 2020. Mar 27. DOI: 10.1016/j.jinf.2020.03.005	Clinical features of COVID-19 in elderly patients: A comparison with young and middle-aged patients	Yes	No details on LPV/r therapeutics
19	Fan Z, Chen L, Li J, Cheng X, Yang J, Tian C, et al. Clinical Features of COVID-19-Related Liver Damage. Clin Gastroenterol Hepatol. 2020. Apr 10. DOI: 10.1016/j.cgh.2020.04.002.	Clinical Features of COVID-19-Related Liver Damage	Yes	No details on LPV/r therapeutics
20	Rosa SGV, Santos WC. Clinical trials on drug repositioning for COVID-19 treatment. Rev Panam Salud Publica. 2020;44:e40.	Clinical trials on drug repositioning for COVID-19 treatment	Yes	Review
21	Martinez MA. Compounds with Therapeutic Potential against Novel Respiratory 2019 Coronavirus. Antimicrob Agents Chemother. 2020;Apr 21. DOI: 10.1128/AAC.00399-20	Compounds with Therapeutic Potential against Novel Respiratory 2019 Coronavirus	Yes	Review
22	Lv DF, Ying QM, Weng YS, Shen CB, Chu JG, Kong JP, et al. Dynamic change process of target genes by RT-PCR testing of SARS-Cov-2 during the course of a Coronavirus Disease 2019 patient. Clin Chim Acta. 2020;506:172-5.	Dynamic change process of target genes by RT-PCR testing of SARS-Cov-2 during the course of a Coronavirus Disease 2019 patient	Yes	No details on LPV/r therapeutics
23	Muralidharan N, Sakthivel R, Velmurugan D, Gromiha MM. Computational studies of drug repurposing and synergism of lopinavir, oseltamivir and ritonavir binding with SARS-CoV-2 protease against COVID-19. J Biomol Struct Dyn. 2020; 16:1-6.	Computational studies of drug repurposing and synergism of lopinavir, oseltamivir and ritonavir binding with SARS-CoV-2 protease against COVID-19	Yes	No details on LPV/r therapeutics
24	Song J, Kang S, Choi SW, Seo KW, Lee S, So MW, et al. Coronavirus Disease 19 (COVID-19) complicated with pneumonia in a patient with rheumatoid arthritis receiving conventional disease-modifying antirheumatic drugs. Rheumatol Int. 2020;40:991-5.	Coronavirus Disease 19 (COVID-19) complicated with pneumonia in a patient with rheumatoid arthritis receiving conventional disease-modifying antirheumatic drugs	Yes	No details on LPV/r therapeutics
25	Wang M, Zhou Y, Zong Z, Liang Z, Cao Y, Tang H, et al. A precision medicine approach to managing 2019 novel coronavirus pneumonia. Precis Clin Med. 2020;3:14-21.	A precision medicine approach to managing 2019 novel coronavirus pneumonia	Yes	No details on LPV/r therapeutics
26	McCreary EK, Pogue JM. Coronavirus Disease 2019 Treatment: A Review of Early and Emerging Options. Open Forum Infect Dis. 2020;7:ofaa105.	Coronavirus Disease 2019 Treatment: A Review of Early and Emerging Options	Yes	Review
27	Yuan J, Zou R, Zeng L, Kou S, Lan J, Li X, et al. The correlation between viral clearance and biochemical outcomes of 94 COVID-19 infected discharged patients. Inflamm Res. 2020;69:599-606.	The correlation between viral clearance and biochemical outcomes of 94 COVID-19 infected discharged patients	Yes	No details on LPV/r therapeutics
28	Han W, Quan B, Guo Y, Zhang J, Lu Y, Feng G, et al. The course of clinical diagnosis and treatment of a case infected with coronavirus disease 2019. J Med Virol. 2020;92:461-3.	The course of clinical diagnosis and treatment of a case infected with coronavirus disease 2019	Yes	No details on LPV/r therapeutics
29	Guzik TJ, Mohiddin SA, Dimarco A, Patel V, Savvatis K, Marelli-Berg FM, et al. COVID-19 and the cardiovascular system: implications for risk assessment, diagnosis, and treatment options. Cardiovasc Res. 2020. Apr 30. DOI:10.1093/cvr/cvaa106	COVID-19 and the cardiovascular system: implications for risk assessment, diagnosis, and treatment option	Yes	Review
30	Sankar J, Dhochak N, Kabra SK, Lodha R. COVID-19 in Children: Clinical Approach and Management. Indian J Pediatr. 2020. Apr 27. DOI: 10.1007/s12098-020-03292-1	COVID-19 in Children: Clinical Approach and Management	Yes	Review
31	Ma J, Xia P, Zhou Y, Liu Z, Zhou X, Wang J, et al. Potential effect of blood purification therapy in reducing cytokine storm as a late complication of critically ill COVID-19. Clin Immunol. 2020;214:108408.	Potential effect of blood purification therapy in reducing cytokine storm as a late complication of critically ill COVID-19	Yes	No details on LPV/r therapeutics
32	Bleasel MD, Peterson GM. Emetine, Ipecac, Ipecac Alkaloids and Analogues as Potential Antiviral Agents for Coronaviruses. Pharmaceuticals (Basel). 2020; Mar 21. DOI: 10.3390/ph13030051.	Emetine, Ipecac, Ipecac Alkaloids and Analogues as Potential Antiviral Agents for Coronaviruses	Yes	Review
33	Arshad Ali S, Baloch M, Ahmed N, Arshad Ali A, Iqbal A. The outbreak of Coronavirus Disease 2019 (COVID-19)-An emerging global health threat. J Infect Public Health. 2020;13:644-6.	The outbreak of Coronavirus Disease 2019 (COVID-19)-An emerging global health threat	Yes	No details on LPV/r therapeutics
34	Cai Q, Huang D, Yu H, Zhu Z, Xia Z, Su Y, et al. COVID-19: Abnormal liver function tests. J Hepatol. 2020. Apr 13. DOI: 10.1016/j.jhep.2020.04.006	COVID-19: Abnormal liver function tests	Yes	No details on LPV/r therapeutics
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