Efficacy and Safety of Leflunomide for Refractory COVID-19: A Pilot Study

Leflunomide treatment for patients hospitalised with COVID-19: DEFEAT-COVID randomised controlled trial

OBJECTIVE

To evaluate the clinical efficacy and safety of leflunomide (L) added to the standard-of-care (SOC) treatment in COVID-19 patients hospitalised with moderate/critical clinical symptoms.

DESIGN

Prospective, open-label, multicentre, stratified, randomised clinical trial.

SETTING

Five hospitals in UK and India, from September 2020 to May 2021.

PARTICIPANTS

Adults with PCR confirmed COVID-19 infection with moderate/critical symptoms within 15 days of onset.

INTERVENTION

Leflunomide 100 mg/day (3 days) followed by 10-20 mg/day (7 days) added to standard care.

PRIMARY OUTCOMES

The time to clinical improvement (TTCI) defined as two-point reduction on a clinical status scale or live discharge prior to 28 days; safety profile measured by the incidence of adverse events (AEs) within 28 days.

RESULTS

Eligible patients (n=214; age 56.3±14.9 years; 33% female) were randomised to SOC+L (n=104) and SOC group (n=110), stratified according to their clinical risk profile. TTCI was 7 vs 8 days in SOC+L vs SOC group (HR 1.317; 95% CI 0.980 to 1.768; p=0.070). Incidence of serious AEs was similar between the groups and none was attributed to leflunomide. In sensitivity analyses, excluding 10 patients not fulfilling the inclusion criteria and 3 who withdrew consent before leflunomide treatment, TTCI was 7 vs 8 days (HR 1.416, 95% CI 1.041 to 1.935; p=0.028), indicating a trend in favour of the intervention group. All-cause mortality rate was similar between groups, 9/104 vs 10/110. Duration of oxygen dependence was shorter in the SOC+L group being a median 6 days (IQR 4-8) compared with 7 days (IQR 5-10) in SOC group (p=0.047).

CONCLUSION

Leflunomide, added to the SOC treatment for COVID-19, was safe and well tolerated but had no major impact on clinical outcomes. It may shorten the time of oxygen dependence by 1 day and thereby improve TTCI/hospital discharge in moderately affected COVID-19 patients.

TRIAL REGISTRATION NUMBERS

EudraCT Number: 2020-002952-18, NCT05007678.

Leflunomide: Traditional immunosuppressant with concurrent antiviral effects

Leflunomide is a classic disease-modifying anti-rheumatic drug that is widely used to treat autoimmune diseases. Studies also show its antiviral effects in in vitro and/or in vivo experiments. Considering glucocorticoids, immunosuppressants and newly emerged antibodies commonly used in autoimmune diseases and autoinflammatory disorders bring risk of infection such as viral infection, leflunomide with combination of anti-viral and immunosuppressive features to maintain the balance between infection and anti-inflammation are attractive. Here we summarize the actions and mechanisms of leflunomide in immunoregulatory and antiviral effects.

COVID-19 among patients with giant cell arteritis: a single-centre observational study from Slovenia

OBJECTIVES

Patients with giant cell arteritis (GCA) represent a fragile population with an increased infection risk. In a recent study, older age, a higher number of comorbidities, higher disease activity and prednisolone ≥ 10 mg/day were associated with worse COVID-19 outcome. We aimed to evaluate the frequency and severity of COVID-19 in a well-defined GCA cohort.

METHODS

We reviewed medical records of histologically and/or by imaging-proven GCA patients diagnosed between September 2011 and February 2020 at our secondary/tertiary centre and followed during the COVID-19 pandemic between March 2020 and February 2022 (24 months). Descriptive statistics were used to explore the studied population.

RESULTS

Of 314 patients with GCA diagnosed for the first time during a 102-month period, 49 patients died before March 2020. Of the remaining 265 patients, 55 (20.8%) patients suffered from a total of 57 SARS-CoV-2 infections. We observed 44 (77.2%) mild and 13 (22.8%) severe COVID-19 episodes (the latter defined as needing hospitalization, death or thrombotic complication). Patients with severe COVID-19 were more likely to have arterial hypertension (12 [92.3%] vs. 25 [56.8%]; p = 0.022), cardiovascular disease (7 [53.8%] vs. 10 [22.7%]; p = 0.043) or obesity (5 [38.5%] vs. 5 [11.4%]; p = 0.038). Neither prednisolone dose 1-5 mg/day (p = 0.483) nor leflunomide use (p = 1.000) was associated with COVID-19 course. There were no significant differences in sex, age, GCA type, GCA disease duration and other comorbidities in patients with mild and severe COVID-19 in our cohort.

CONCLUSION

More than a fifth of our GCA patients had severe COVID-19. Treatment with leflunomide or low doses of glucocorticoids were not associated with severe course in our cohort. Key Points • Treatment with leflunomide or low doses of glucocorticoids were not associated with worse COVID-19 outcome. • Outcomes of COVID-19 improved as the COVID-19 pandemic, prevention and treatment options evolved. • Arterial hypertension, cardiovascular disease or obesity were associated with severe COVID-19.

Significance of Immune Status of SARS-CoV-2 Infected Patients in Determining the Efficacy of Therapeutic Interventions

Coronavirus disease 2019 (COVID-19) is now being investigated for its distinctive patterns in the course of disease development which can be indicated with miscellaneous immune responses in infected individuals. Besides this series of investigations on the pathophysiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), significant fundamental immunological and physiological processes are indispensable to address clinical markers of COVID-19 disease and essential to identify or design effective therapeutics. Recent developments in the literature suggest that deficiency of type I interferon (IFN) in serum samples can be used to represent a severe progression of COVID-19 disease and can be used as the basis to develop combined immunotherapeutic strategies. Precise control over inflammatory response is a significant aspect of targeting viral infections. This account presents a brief review of the pathophysiological characteristics of the SARS-CoV-2 virus and the understanding of the immune status of infected patients. We further discuss the immune system’s interaction with the SARS-CoV-2 virus and their subsequent involvement of dysfunctional immune responses during the progression of the disease. Finally, we highlight some of the implications of the different approaches applicable in developing promising therapeutic interventions that redirect immunoregulation and viral infection.