RESUMEN
Background: Molnupiravir, a prodrug of the broadly active, direct-acting antiviral, ribonucleoside analogue EIDD-1931, is a promising COVID-19 drug. Given the primary route of SARS-CoV-2 transmission through respiratory droplets we evaluated EIDD-1931 PK in saliva, nasal secretions and tears of patients with mild-to-moderate COVID-19 through the phase Ib/IIa AGILE platform (NCT04746183). Methods: Patients with PCR-confirmed SARS-CoV-2 infection, within 5 days of symptom onset with mild-to-moderate disease were randomised to oral molnupiravir 300, 600 or 800 mg twice daily. Plasma and non-plasma (saliva, nasal and tear swabs) samples were collected pre-dose, 0.5, 1, 2, and 4 hours post-dose on study days 1 and 5 and molnupiravir and EIDD-1931 measured by LC/MS (lower limit of quantification, 2.5 ng/mL). PK parameters were determined (Phoenix 64, WinNonlin, v. 8.3) and non-plasma:plasma (NP:P) ratios (based on AUC0-4) calculated. Relationships between paired non-plasma and plasma samples were evaluated by linear regression. Results: Twelve participants (n=4 per dose;75% female) completed the study contributing 111, 112 and 97 saliva, nasal and tear samples, respectively. Molnupiravir was detected in 11% of saliva samples [median (range) 4.86 ng/mL (2.63-31.44)] and not evaluated in swabs. Quantifiable EIDD-1931, following molnupiravir 300, 600 and 800 mg twice daily were i) saliva: 17.7 (2.8-133), 16.6 (2.9-469), 25.8 (4.0-230) ng/mL, ii) nasal swabs: 182 (18-1700), 136 (18-917), 295 (24-1879) ng/mL and iii) tears: 297 (24-1650), 176 (16-1260), 307 (32-2760) ng/mL. PK parameters are shown (Table 1). Median (range, CV%) pooled NP:P ratio for saliva was 0.03 (0.01-0.11, 60%;n=16). Nasal and tear ratios were 6-fold higher with values of 0.21 (0.05-0.73, 70%;n=17) and 0.22 (0.09-1.05, 92%;n=12), respectively. Non-plasma and plasma concentrations were significantly correlated (r2: 0.360-0.677;p<0.0001). Of measured saliva, nasal and tear samples, 6, 50 and 61%, respectively were within or above the EIDD-1931 EC90 against SARS-CoV-2 in primary human airway epithelia cultures (approximately 0.5-1 μ M ≈ 130-260 ng/mL). Conclusion: This is the first report of EIDD-1931 PK at sites of initial SARS-CoV-2 exposure in patients with COVID-19. Investigations of PK/PD relationships are warranted;however, these data suggest therapeutic concentrations are potentially achieved in nasal and tear compartments, but not saliva and have important implications for prophylactic coverage.
RESUMEN
Background: The emergence of SARS-CoV-2 viral variants threatens current anti-viral and preventative strategies, including monoclonal antibodies and vaccines. Critically, the limited supply of vaccines and the complex logistics surrounding the delivery of infusion-based therapies herald the need for an easily produced, distributed, and specific direct-acting antiviral for COVID-19 that limits progression of illness and ideally prevents transmission. Methods: The efficacy of molnupiravir was evaluated in a double-blind, randomized, placebo-controlled, Phase 2 dose-range finding study using realtime polymerase chain reaction (RT-PCR) and virus isolation was conducted at 11 study sites in the U.S. Participants were randomized if they had signs or symptoms of COVID-19 within 7 days, and a positive SARS-CoV-2 RT-PCR within 4 days of enrollment. Initially, participants were randomized in a 1:1 ratio to receive 200 mg molnupiravir or placebo twice daily for 5 days. Subsequently, in the dose-range finding portion of the study, participants were randomized in a 3:1 ratio to receive 200, 400, or 800 mg molnupiravir or placebo twice daily for 5 days. Nasopharyngeal swabs were analyzed from 175 subjects at enrollment, Day 3, and Day 5 for SARS-CoV-2 infectivity. Samples were stored at 4°C for up to 72 hours, shipped refrigerated, aliquoted, and stored at -80°C until testing. Vero E6 cell monolayers were infected with the sample for 1 hour. Culture medium was analyzed for viral load at 2 and 5 days post-infection by RT-PCR. Results: Seventy-eight (45%) participants, median 4.62 days (min. 1.40, max. 7.54) from symptom onset, had a positive SARS-CoV-2 culture at enrollment (52 on active and 26 on placebo). The percentage of participants with a positive viral culture at enrollment who were positive on Day 3 was 20.4% on active and 28% on placebo (p = 0.56). At day 5, 24% of placebo participants were culturethe positive compared to none treated with molnupiravir (p = 0.001). Between treatment, comparisons were performed using Fisher's exact test. Conclusion: This is the first demonstration of reduced infectiousness by antiviral therapy in people with SARS-2 infection. This simple, short-course oral therapy may benefit individuals and public health and is unlikely to be impacted by spike-protein variants.