Phase 3 SCALP Study on Clascoterone for Androgenetic Alopecia, With Maria Hordinsky, MD

New topline, phase 3 findings from the SCALP 1 and 2 studies have been released by Cosmo Pharmaceuticals suggesting clascoterone may be an effective medication for men living with androgenetic alopecia.1

Androgenetic alopecia, commonly referred to as male pattern hair loss, would have the first new therapeutic agent in over 3 decades if clascoterone were to receive approval by the US Food and Drug Administration (FDA).2 Clascoterone solution was formulated to target androgenetic alopecia via a novel biological pathway, selectively binding to androgen receptors in the skin and scalp.

Both SCALP 1 and SCALP 2 attained statistically significant endpoints in Target-Area Hair Count (TAHC) results.1 To discuss these new findings on clascoterone and androgenetic alopecia, the HCPLive editorial team spoke with Maria Hordinsky, MD, an RW Goltz Professor of Dermatology at the University of Minnesota, along with Diana Harbort of Cosmo Pharmaceuticals. Hordinsky and Harbort highlighted a variety of key points from the data:

HCPLive: Would you speak with us about the trial design itself and what these studies assessing clascoterone looked like?

Hordinsky: We here at the University of Minnesota were engaged in this particular clinical trial, and it was a trial where patients were applying the topical medication twice a day. The data that is out there is from the first 6 months. There is still another 6 months of data that is under review at present. We were blinded, like all the sites, as to whether or not a participant was receiving the actual drug or not. This is where I'm going to turn to Diana, because Diana can talk about the 2 studies [in depth]. There are 2 different studies examining the same clinical trial goals. Can you comment on that?

Harbort: The phase 3 program for clascoterone solution contained 2 identical in design trials. These were multi-center, prospective, randomized, 2-to-1 vehicle-controlled studies with either the vehicle or the study drug being delivered BID. The study enrolled 1465 patients with mild to moderate AGA in 51 sites across the US and Europe. Scalp 1 is the pivotal part of the program, which is meant for just the first 6 months of treatment, and the goal is to evaluate the safety and efficacy of the drug versus the vehicle.

Scalp 2 is identical in design to the first 6 months to also evaluate the safety and efficacy. So part 1 is the pivotal part, and part 2 is the safety extension part, where patients roll over from scalp one or scalp to the responders' rollover into the second 6 months of the trial. The goal of that is to determine the long-term safety and durability of the treatment. In part one, the co-primary efficacy endpoints are the TAHC and the patient-reported outcomes.

HCPLive: Would either of you explain some of the most notable findings for the 6 months of treatment with clascoterone and androgenetic alopecia?

Hordinsky: From an investigator's point of view, the findings are outstanding in that sense that the total number of hair counts in the areas that were mentioned increased greatly. I can tell, just in our own institution, and the patients who participated with us, again, didn't know what they were on, and neither did we. When you see improvement, you assume that the patient has been on the actual medication. Patients found the medication to be tolerable.

If you look at the safety data across the entire studies, both studies to date, the safety profile is very good, with minimal irritation to the skin from the use of the topical product and, most importantly, very few systemic or internal side effects. We're dealing here with a topical agent that targets testosterone and the receptor, so when you start to think about medications that might impact hormones, we're talking about something that really impacts hormones in the skin alone. Another very important point from this particular study is that there were very there were no significant sexual side effects related to the use of this topical medication twice a day.

HCPLive: In light of what you have said, what are some of the most notable concerns patients might have regarding some unmet needs related to existing treatments?

Hordinsky: I can speak from personal experience in the clinic. When a person comes in who's in their early twenties and is starting to develop early pattern alopecia, or androgenic alopecia, also known as male pattern baldness, then one has to think, ‘What can we do at that particular stage?’ At this time, we have 2 approved medications. We have topical minoxidil, or Rogaine in a liquid or foam preparation, and we have an oral medication called finasteride, which blocks the conversion of testosterone to dihydrotestosterone.

I just gave the example of someone in their early 20s taking a pill that, more recently, has risen to the top of social media in terms of having significant side effects. With topical minoxidil, it does work, but as has been pointed out, this medication was approved almost 30 years ago, so we have basically 2 medications that we can really talk about that are FDA-approved to that young person sitting there talking about how to prevent hair loss.

Our other options when we're in clinic we’ll be to talk about are devices like red light therapy, which you have to do a few times per week, or something like platelet-rich plasma. We don't talk about hair transplantation in those early stages, but we do talk about how, if you don't do anything, we really don't know how far this hair loss is going to extend…So that young patient in the clinic is getting a lot of information about a lot of different approaches to treating male pattern hair loss or androgenetic alopecia. That's why this new topical is so exciting, because it's a completely different mechanism of action. It's topical, and the 6-month data looks really, really good.

References

1. Cosmo announces breakthrough Phase III Topline results from Scalp 1 and Scalp 2 for Clascoterone 5% Solution in male hair loss, showing up to 539% relative improvement in Target-Area Hair Count vs placebo; US and EU submissions are underway. Cosmo Pharmaceuticals. December 3, 2025. Accessed: December 18, 2025. https://www.cosmopharma.com/news/cosmo-announces-breakthrough-phase-iii-topline-results-from-scalp-1-and-scalp-2-for-clascoterone-5-solution-in-male-hair-loss-showing-up-to-539-relative-improvement-in-target-area-hair-count-vs-place.

2. Chen S, Li L, Zhou N, et al. Androgenetic alopecia: An update on pathogenesis and pharmacological treatment. Drug Des Devel Ther. 2025 Aug 25;19:7349-7363. doi: 10.2147/DDDT.S542000.