Category Archives: Setipiprant

Kythera and Replicel Updates

Replicel’s latest presentation from BioAsia 2015 in Japan is out.  I was not planning on writing much about Replicel for a few months, but it seems like they keep making interesting presentations almost every month with some new information each time. Moreover, people in the hair loss chat on this site keep asking about Replicel.

At the start of the presentation, I liked reading the quote from Japanese prime minister Shinzo Abe that was made in early 2014:

Japan is on the leading edge in regenerative medicine. We will make it possible to generate cells at private-sector factories.

Page 16-19 has most of the RCH-01 and 6-month hair growth related information.  12-month results with higher doses and frequency will likely lead to better outcomes as has been conjectured in the past.  The last part of the presentation has more details on Japan’s regenerative medicine reforms (via Abenomics related policy changes) and early-to-market reforms.

More interesting to me was this week’s news regarding Kythera Biopharmaceuticals’ ATX-101 injectable drug that reduces double chins receiving unanimous backing from an independent panel of experts.  It is thus likely that the FDA will approve this product in the next several months, and if effective, it could in some cases become a better alternative to liposuction.  In fact ATX-101 (brand name Kybella) would be the first ever drug to be approved by the FDA to reduce localized fat deposits.  This company’s stock price movement is definitely worth following.

The main reason I found this news interesting is because just over a month ago, Kythera Biopharmaceuticals acquired global rights to Setipiprant, a PGD2 antagonist.  According the company’s highly informative 2013 annual report and per various parts of the company’s website, it seems like hair and fat are two of the main areas in which Kythera will be focusing on in the coming years, with an overall focus on the human face.  The company has a long-term goal of becoming a major player in the aesthetics industry.

For those interested, Kythera has an investor conference call and webcast later today at 4:30 pm ET.

Kythera Biopharmaceuticals Purchases Global Rights to Setipiprant

Update: Kythera audio interview with founder and CEO Keith Leonard regarding Setipiprant and the company’s recent history of hair loss research is now out.  Excellent stuff!


Kythera (now part of Allergan)

A thus far barren February when it comes to significant hair loss research developments suddenly changed drastically today. It was announced that Kythera Biopharmaceuticals (US) has purchased global rights to Setipiprant, a clinical-stage oral antagonist to the prostaglandin D2 (PGD2) receptor.

The shareholder presentation on this is a must read. Rights were purchased via licensing agreements with Actelion Pharmaceuticals (Switzerland) and the University of Pennsylvania. A good summary is here, with a very encouraging quote from Kythera’s Chief Medical Officer:

Setipiprant is believed to directly affect this hair loss pathway, and our own preclinical and in vitro human hair models confirmed this effect. It is a well-characterized molecule with a large safety database and we believe we can quickly initiate a development program to study it in hair loss.

According to the investor presentation, Setipiprant has already undergone 8 clinical trials, including:

  • A Phase III study in seasonal allergic rhinitis patients.
  • A Phase IIB proof of concept study in asthma patients.
  • A safety database of over 1,000 subjects.

One other item in the investor presentation that I found shocking (in a very good way) was that Actelion owns 45 patents that were granted for molecules that inhibit PGD2. So Setipiprant is just one molecule of perhaps dozens or even hundreds that can inhibit PGD2.

There must be other companies that also have patents to proprietary PGD2 antagonist molecules. I wonder if they can introduce their products into the hair loss market in future if they do not have licensing agreements with the University of Pennsylvania?


PGD2 has been in the news a lot in the hair loss world during the past several years, in large part due to Dr. Luis Garza’s (and Ashley Nieves’) work and excellent publicly available 2014 paper on the subject, as well as past work of Dr. George Cotsarelis and his team at the University of Pennsylvania.

Both Cotsarelis and Garza were part of a large group of authors of an important 2012 paper which concluded that PGD2 inhibits hair growth and was elevated on the scalps of balding men. Together, these two men are also considered to be co-inventors/co-founders of this PGD2-receptor pathway that inhibits hair growth. The patent for this technology is owned by the University of Pennsylvania, hence their involvement in this current transaction.

It seems like the PGD2-GPR44 pathway (PGD2 binds to the GPR44 receptor) is responsible for hair growth inhibition, and any drug to regrow hair will target GPR44. More significantly, PGD2 is also involved in asthma, allergies and related medical disorders. In fact a number of drugs targeting PGD2 are already in advanced clinical trials or even on the market, so there should already be a good deal of safety information on this type of product.

I found seven studies on Setipiprant on Pubmed as of today. Also, some popular media articles from 2012 on PGD2 and a hair loss cure are worth a reread: Dailymail,  The Telegraph and NY Times. Unfortunately we are still not close to getting a topical lotion cure, since Setipiprant is an oral medication.

For the neglected female readers of this blog, it seems like there is a very good chance that this same drug could also cure female pattern hair loss. PGD2 appears to curtail hair growth in both men and women.

Finally, a bit about Los Angeles area based publicly traded Kythera from their website. Where else would one expect a biopharma company to focus on eliminating double chins?

Our product candidate, ATX-101, is a potential first-in-class, injectable drug currently in late-stage clinical development for the reduction of submental fat, which commonly presents as an undesirable “double chin.” We maintain an active research interest in hair and fat biology, pigmentation modulation and facial contouring.

One-year stock price trend of ticker KYTH. Edit: No longer traded, since being acquired by Allergan.