A Single-Center, Double-Blind, Randomized, Placebo-Controlled, Two-Arm Study To Evaluate The Safety And Efficacy Of Once-Weekly Sirolimus (Rapamycin) On Muscle Strength And Endurance In Older Adults Following A 13-Week Exercise Program
Research Summary
This paper is the published protocol of RAPA-EX-01, a randomised, double-blind, placebo-controlled trial built on the ‘cycling hypothesis’ – alternating mTORC1 inhibition with rest-day sirolimus and mTORC1 activation with exercise, in the hope of keeping or amplifying training gains in older muscle. It describes the design and reports no results.
Who Or What Was Studied?
The trial plans to enrol 40 community-dwelling adults aged 65 to 85, randomised 1:1 to once-weekly oral sirolimus (rapamycin) 6 mg or a matched placebo for 13 weeks, with the same at-home exercise programme in both arms. Outcomes are assessed at baseline, week 6 and week 13: the primary endpoint is the change in 30-Second Chair-Stand Test repetitions, secondary endpoints are the 6-minute walk test, handgrip strength and the SF-36 survey. Scheduled blood work covers full blood count, urea and electrolytes, liver function tests, HbA1c, lipids, serum IGF-1 and hs-CRP, and DNA methylation is analysed through TruDiagnostic to explore change in biological age. The trial is registered ACTRN12624000790549.
What Did The Research Show?
- The protocol specifies sirolimus 6 mg once weekly, taken on day 6 of each training week, about 24 hours after the last exercise session, for 13 weeks.
- The primary endpoint is the change in 30-second chair-stand repetitions; 6-minute walk distance, grip strength and SF-36 scores are the secondary functional outcomes.
- Safety is a co-focus of the design: adverse events plus haematology and biochemistry panels, HbA1c, lipids, IGF-1 and hs-CRP are all built into the schedule.
- DNA methylation testing is part of the protocol, so biological-age measures are collected alongside the functional tests.
- Funding comes from the lead author’s own company and Vitasang Ltd, and trial conduct is separated from the sponsor through an independent trust and a contract research organisation.
Limitations And Interpretation
- This is a study protocol: no outcome data are reported, so it cannot say whether the regimen works or is safe in practice.
- Forty participants at a single centre make the trial exploratory rather than definitive.
- The results of this trial were published separately in 2026; any conclusion about effects should rest on that results paper, not on this design paper.
- Nothing in the protocol supports a dosing recommendation for individuals.
Summary prepared from the published paper (abstract and full text where accessible). This is not medical advice — always consult the original publication.