Can You Explain the RepliCel Phase 1 Before and After Photos?
dear doctor
i have heard about the news of replicel. i searched their website and found something weird. In their paper, there are two photos in the first page, but i cannot see any change in hair density as they claim. Can you explain it to me? thanks
I do not know much about this, but based on what you linked to, it looks like they are proposing to test 108 men in phase 2 (it does not seem like this has been done). As they word it, it is “anticipated that implanted cells will migrate to damaged or dormant follicles and help rejuvenate them“. They do not mention the science. They seem to stress the monetary dollar amount of the hair loss market (more so than the science), so they are likely looking for investors.
Finally, I do not see much hair density in the photo myself, at least not visibly/cosmetically. Perhaps someone else more informed about RepliCel can provide more.
From the link, they are conducting a Phase 1 study in Europe – typically done to assess safety- and do not specify how many patients this study included. The term “Phase 1/2a†implies that they also are evaluating preliminary efficacy (the 2a) but that the study was not “powered†to detect efficacy as the main goal (ie a study might miss true efficacy because of the small number of patients). Besides a lack of info on this study (number of patients, duration of observation), they clearly state that the study is still ongoing (not completed) and that the results they describe are from an “early look†(interim analysis) before completion of the study. These efficacy results thus must be taken as highly preliminary, common for these types of early studies to mainly establish safety (the ability to take “interim†looks would be more discouraged in a Phase 2 trial where the investigators must be unaware of treatment assignment to avoid bias). It is also important that only 63% of the trial participants responding to the treatment, and the summary results they mention are in these 63%. A more traditional analysis would also evaluate the changes in all participants, which then gives a more accurate assessment of the likelihood of results. I would also be interested in how they defined a “non-responder†(37% of study participants). So, the photo is just a representative diagram of one responder without a lot of detail.
As Dr R said, the Phase 2 study – which presumably is powered to detect treatment differences – is proposed and has not yet begun. This is where the company will (according to the link) test different regimens in a placebo-controlled stetting and where the “real†efficacy (in an adequately powered study) will be determined. At this point, the reader should assume the procedure is safe, which is why the company mentions that they have been given the green light to proceed to a controlled Phase 2 study. The results of the Phase 2 study – yet to be begun – will establish whether the procedure is effective. So, everyone will have to wait!
Added comment: the Phase 1/2a study is 6 months in duration for each patient. The interm look evaluated a certain number of patients who completed their 6-month assessments (and other patients have yet to complete).