(3.2%) report COVID19 symptoms on D90, (3.4%) on D120, (2.6%) on D180. adjusted risk of PASCD on day 180 was lower in metformin group (โ0.008; posterior probability of efficacy [PPE] 0.83), compared with placebo group with aRR of 0.79. risk of clinician diagnosis of long COVID (secondary outcome) on D180 was lower in metformin group (โ0.007; PPE 0.96), with RR of 0.495