Translational stewardship in pandemic therapeutics: ivermectin, evidentiary misalignment, and the propagation of constraints
摘要
The COVID-19 pandemic exposed a recurring vulnerability within translational medicine: early therapeutic signals can acquire clinical, public, and institutional authority before the evidentiary pathway has established pharmacologic plausibility, evidence quality, clinical efficacy, and appropriate use. This Commentary proposes translational stewardship as an upstream response. Its central claim is that positive therapeutic signals and their critical plausibility constraints should co-travel through the translational pathway. A positive biological signal and a clinically plausible therapeutic signal are different evidentiary objects; when that distinction is lost, perceived therapeutic readiness can exceed evidentiary maturity. Ivermectin provides a concentrated case study. An initial in vitro antiviral finding generated a legitimate but low-confidence repurposing signal, while subsequent pharmacokinetic and pharmacodynamic analyses substantially constrained the plausibility of direct antiviral efficacy at clinically achievable exposures. Early clinical evidence was heterogeneous and fragile, portions of the evidence base were later affected by data-integrity concerns, and larger randomized trials did not demonstrate clinically meaningful benefit. Nevertheless, ivermectin acquired credibility through unstable evidence synthesis, clinical advocacy, public amplification, and institutional-distrust narratives. The broader lesson is not that early signals should be suppressed, but that critical constraints should be encoded, preserved, and propagated before provisional findings acquire durable therapeutic authority.