Background: Post-trial provisions (PTP), including post-trial access (PTA), are core obligations under international guidelines, yet often weakly specified and inconsistently documented. We examined their public verifiability in COVID-19 trials reviewed in Brazil. Methods: We conducted a documentary audit of interventional COVID-19 trials approved by Brazil’s National Research Ethics Commission (CONEP) in 2020–22, identified through the Observatório Plataforma Brasil. From publicly accessible sources only, we sought protocols and informed consent forms (ICFs), distinguishing document availability, public verifiability of PTP (affirmative or negative information in retrieved documents), and substantive commitments. Associations were estimated as prevalence ratios (PRs; Poisson regression with robust variance). Findings: Of 297 trials, no protocol or ICF was publicly available for 258 (86·9%); documents were retrieved for 39 (13·1%), of which 29 (9·8%) contained PTP information. Availability was higher in vaccine than non-vaccine trials (PR 2·46, 95% CI 1·37–4·42) and lower for repurposed drugs than new molecular entities (8·3% vs 19·8%); chloroquine, hydroxychloroquine, or azithromycin trials were least available (1/26). The commonest content was that no PTA would be provided (n=15) or no PTP information (n=10); two vaccine trials offered the study vaccine to placebo recipients after emergency-use authorisation; none documented unconditional post-trial supply. Interpretation: Most trials had no publicly available protocol or ICF, and PTP were verifiable for fewer than one in ten—an accountability gap centralised ethics oversight alone does not close. Public access to protocols and ICFs as a condition of approval is needed to make post-trial obligations auditable.