It looks like we have the (preliminary, preprint) results of our first RCT of renin-angiotensin blockers for the treatment of COVID-19. Some of my early thoughts 1/ https://www.medrxiv.org/content/10.1101/2020.08.04.20167205v1

2/ First, the authors planned to enroll n=400. Here, they present preliminary data on the 1st 78 analyzed participants based on a planned interim analysis on July 31. My understanding, based on labeling this as a "preliminary report", is that this trial is ongoing

3/ As @DrToddLee points out, it's unclear if there were any stopping rules set for this interim analysis. The purpose of the interim analysis is unclear. Also unclear how this early peek at the data will affect the study moving forward (more on this later) https://twitter.com/DrToddLee/status/1293375723881865216?s=20

4/ Let's look at the design. This is an unblinded RCT. I hope the authors misspoke re: "no concealment" because randomization without allocation concealment is no randomization at all. Simple randomization also isn't ideal with a small sample

5/ Next, the authors mention CRP as 1ary outcome. However, on http://clinicaltrials.gov , "need for supplemental O2 within 15 days" was originally registered as their 1ary outcome. CRP was only a 3ary outcome. Without clarification, this is concerning for outcome reporting bias

6/ On to the outcomes. 65/78 (83%) of participants required supplemental O2 at baseline, so I can see why their original 1ary outcome was problematic

For CRP, @DrToddLee highlights the high n missing CRP data at days 5/8; missingness ins't likely random. https://twitter.com/DrToddLee/status/1293378608082362371?s=20

7/ The authors report shorter time to discharge in telmisartan vs control group & more discharged by day 15... but with the huge caveat of bias due to not being blinded, & based on the present report, unclear implementation of randomization.

8/8 The authors are no doubt excited about these early findings. In their shoes, I'd have difficulty remaining impartial after this peek. With no blinding & ?concealment, it's unclear to me how the rest of this trial can continue without being influenced by this early peek