Optimal dose and safety of molnupiravir in patients with early SARS-CoV-2: a Phase I, open-label, dose-escalating, randomized controlled study

OBJECTIVES

AGILE is a Phase Ib/IIa platform for rapidly evaluating COVID-19 treatments. In this trial (NCT04746183) we evaluated the safety and optimal dose of molnupiravir in participants with early symptomatic infection.

METHODS

We undertook a dose-escalating, open-label, randomized-controlled (standard-of-care) Bayesian adaptive Phase I trial at the Royal Liverpool and Broadgreen Clinical Research Facility. Participants (adult outpatients with PCR-confirmed SARS-CoV-2 infection within 5 days of symptom onset) were randomized 2:1 in groups of 6 participants to 300, 600 and 800 mg doses of molnupiravir orally, twice daily for 5 days or control. A dose was judged unsafe if the probability of 30% or greater dose-limiting toxicity (the primary outcome) over controls was 25% or greater. Secondary outcomes included safety, clinical progression, pharmacokinetics and virological responses.

RESULTS

Of 103 participants screened, 18 participants were enrolled between 17 July and 30 October 2020. Molnupiravir was well tolerated at 300, 600 and 800 mg doses with no serious or severe adverse events. Overall, 4 of 4 (100%), 4 of 4 (100%) and 1 of 4 (25%) of the participants receiving 300, 600 and 800 mg molnupiravir, respectively, and 5 of 6 (83%) controls, had at least one adverse event, all of which were mild (≤grade 2). The probability of ≥30% excess toxicity over controls at 800 mg was estimated at 0.9%.

CONCLUSIONS

Molnupiravir was safe and well tolerated; a dose of 800 mg twice daily for 5 days was recommended for Phase II evaluation.

AGILE-ACCORD: A Randomized, Multicentre, Seamless, Adaptive Phase I/II Platform Study to Determine the Optimal Dose, Safety and Efficacy of Multiple Candidate Agents for the Treatment of COVID-19: A structured summary of a study protocol for a randomised platform trial

OBJECTIVES

Phase I - To determine the optimal dose of each candidate (or combination of candidates) entered into the platform. Phase II - To determine the efficacy and safety of each candidate entered into the platform, compared to the current Standard of Care (SoC), and recommend whether it should be evaluated further in a later phase II & III platforms.

TRIAL DESIGN

AGILE-ACCORD is a Bayesian multicentre, multi-arm, multi-dose, multi-stage open-label, adaptive, seamless phase I/II randomised platform trial to determine the optimal dose, activity and safety of multiple candidate agents for the treatment of COVID-19. Designed as a master protocol with each candidate being evaluated within its own sub-protocol (Candidate Specific Trial (CST) protocol), randomising between candidate and SoC with 2:1 allocation in favour of the candidate (N.B the first candidate has gone through regulatory approval and is expected to open to recruitment early summer 2020). Each dose will be assessed for safety sequentially in cohorts of 6 patients. Once a phase II dose has been identified we will assess efficacy by seamlessly expanding into a larger cohort.

PARTICIPANTS

Patient populations can vary between CSTs, but the main eligibility criteria include adult patients (≥18 years) who have laboratory-confirmed infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We will include both severe and mild-moderate patients defined as follows: Group A (severe disease) - patients with WHO Working Group on the Clinical Characteristics of COVID-19 infection 9-point ordinal scale of Grades 4 (hospitalised, oxygen by mask or nasal prongs), 5 (hospitalised, non-invasive ventilation or high flow oxygen), 6 (hospitalised, intubation and mechanical ventilation) or 7 (hospitalised, ventilation and additional organ support); Group B (mild-moderate disease) - ambulant or hospitalised patients with peripheral capillary oxygen saturation (SpO2) >94% RA. If any CSTs are included in the community setting, the CST protocol will clarify whether patients with suspected SARS-CoV-2 infection are also eligible. Participants will be recruited from England, North Ireland, Wales and Scotland.

INTERVENTION AND COMPARATOR

Comparator is the current standard of care (SoC), in some CSTs plus placebo. Candidates that prevent uncontrolled cytokine release, prevention of viral replication, and other anti-viral treatment strategies are at various stages of development for inclusion into AGILE-ACCORD. Other CSTs will be added over time. There is not a set limit on the number of CSTs we can include within the AGILE-ACCORD Master protocol and we will upload each CST into this publication as each opens to recruitment.

MAIN OUTCOMES

Phase I: Dose limiting toxicities using Common Terminology Criteria for Adverse Events v5 Grade ≥3 adverse events. Phase II: Agreed on a CST basis depending on mechanism of action of the candidate and patient population. But may include; time to clinical improvement of at least 2 points on the WHO 9-point category ordinal scale [measured up to 29 days from randomisation], progression of disease (oxygen saturation (SaO2) <92%) or hospitalization or death, or change in time-weighted viral load [measured up to 29 days from randomisation].

RANDOMISATION

Varies with CST, but default is 2:1 allocation in favour of the candidate to maximise early safety data.

BLINDING (MASKING)

For the safety phase open-label although for some CSTs may include placebo or SoC for the efficacy phase.

NUMBERS TO BE RANDOMISED (SAMPLE SIZE)

Varies between CSTs. However simulations have shown that around 16 participants are necessary to determine futility or promise of a candidate at a given dose (in efficacy evaluation alone) and between 32 and 40 participants are required across the dose-finding and efficacy evaluation when capping the maximum number of participants contributing to the evaluation of a treatment at 40.

TRIAL STATUS

Master protocol version number v5 07 May 2020, trial is in setup with full regulatory approval and utilises several digital technology solutions, including Medidata's Rave EDC [electronic data capture], RTSM for randomisation and patient eConsent on iPads via Rave Patient Cloud. The recruitment dates will vary between CSTs but at the time of writing no CSTs are yet open for recruitment.

TRIAL REGISTRATION

EudraCT 2020-001860-27 14th March 2020 FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

HATRIC: a study of Pelargonium sidoides root extract EPs®7630 (Kaloba®) for the treatment of acute cough due to lower respiratory tract infection in adults-study protocol for a double blind, placebo-controlled randomised feasibility trial

Background

Acute lower respiratory tract infection is a common acute infection managed in primary care. The current dominant management strategy in the UK is antibiotics, despite widespread publicity regarding antimicrobial resistance and evidence that the small benefits of antibiotics do not outweigh the harms. There is a need to address the rising problem of antibiotic resistance by providing credible alternative strategies, which reduce symptom burden. There is sufficient evidence to recommend the use of Pelargonium sidoides root extract in order to warrant undertaking an independent clinical trial.

We propose a feasibility study to demonstrate our ability to recruit and retain patients and conduct a placebo-controlled trial of Pelargonium sidoides extract EPs®7630 in lower respiratory tract infection where pneumonia is not suspected. Both the tablet and liquid formulations will be included.

Methods

The HATRIC trial is a double-blind randomised placebo-controlled feasibility study aiming to determine the potential to conduct a fully powered trial of Pelargonium sidoides root extract as an alternative to the inappropriate use of antibiotics for acute bronchitis in UK primary care.

Primary care sites will be equally randomised to one of two formulation groups (tablet or liquid preparation). Additionally, within each site, patients will be evenly randomised to active or placebo treatment. Antibiotic consumption will be monitored during the trial, but the use of a delayed prescription strategy is encouraged. The target sample size for this study is 160 patients overall or 40 per arm, recruited from approximately 20 primary care sites. The analysis will be descriptive focusing on estimation with no formal comparison of groups taking place.

Discussion

If this trial demonstrates the feasibility of recruitment and delivery, we will seek funding for a fully powered placebo-controlled trial of Pelargonium sidoides root extract for the treatment of lower respiratory tract infections in primary care.

Trial registration

HATRIC was registered on the ISRCTN registry (ISRCTN17672884) on 16 August 2018.