A RANDOMIZED CONTROLLED TRIAL of CAMOSTAT in OUTPATIENTS with COVID-19

ABSTRACT

Background: Camostat, an oral protease inhibitor, blocks entry and replication of SARS-CoV-1 and SARS-CoV-2 in vitro. It is approved for therapy of recurrent pancreatitis in several countries. Camostat has an excellent safety profile and repurposing for COVID-19 treatment was proposed. Methods: We conducted a Phase II randomized, placebo-controlled trial of camostat in adult outpatients with confirmed COVID-19 and one or more risk factors for severe disease (including age ≥65 years, severe obesity, hypertension, diabetes, chronic lung, heart or liver disease). Participants were randomized 21 to oral camostat 200 mg or matching placebo four times a day for 14 days. Exclusion criteria were end-stage liver disease, severe renal impairment, oxygen saturation ≤94% on room air, and experimental treatment for COVID-19. The primary efficacy endpoint was hospitalization or death within 28 days. Secondary efficacy included positivity for SARS-CoV-2 by PCR on mid-nasal turbinate swabs on days 7 and 15 compared to baseline. Results: We enrolled 295 participants, 57.3% were female, 15.6% Black and 60% Latinx. Mean age was 51 years (18-93 years). Most (75.3%) were randomized ≤5 days after symptom onset. Common risk factors were hypertension (63.4%), chronic lung disease (33.2%) and diabetes (25.4%), with 46.8% having >1 risk factor. With a lower than anticipated event rate, the primary endpoint of hospitalization or death was not significantly different in the camostat (5.3%, 10/194) and placebo groups (6.1%, 6/99;p=0.78). In the intention-to-treat population, there was a trend towards a lower proportion of PCR positivity in the camostat compared to the placebo group at day 7 (65.2% vs. 75.7%, p=0.12) and day 15 (22.0% vs. 34.3%, p=0.06). Similarly, in a post hoc as treated population, fewer participants in the camostat than in the placebo group remained PCR positive at day 7 (64.7%, 88/136 vs. 76.8%, 53/96;p=0.077) and day 15 (21.8%, 29/133, vs. 34.8%, 23/66;p=0.05). Adverse events occurred in 13% of participants in the placebo and 9% in the camostat group. All severe adverse events (5% in both groups) were related to COVID-19. Conclusion: With a low overall event rate, we did not observe a decrease in risk of hospitalization or death in camostat treated outpatients with COVID-19 at risk for severe disease. SARS-CoV-2 PCR turned negative faster on camostat treatment. Camostat was well tolerated.