Category Archives: PGD2

Allergan, Kythera Biopharmaceuticals, PGD2, PGE2, Platelet-Rich Plasma, Prostaglandin D2, Prostaglandin E2, PRP

Allergan Purchases Kythera Biopharmaceuticals

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Allergan Purchases Kythera

The biggest news so far this month is Allergan’s purchase of Kythera Biopharmaceuticals yesterday. While Allergan is largely known for its blockbuster Botox product, the company’s Bimatoprost product is what we hair loss sufferers care about. While Kythera’s most well known product is its recently approved ATX-101 (brand name Kybella) china fat reducing topical product, the company’s Setipiprant product is what we hair loss sufferers care about.

Bimatoprost is essentially (but not exactly) a prostaglandin E2 (PGE2) analog and Setipiprant is a prostaglandin D2 (PGD2) antagonist. The latter holds far greater potential to be a cure for hair loss compared to the former. A combination treatment with the two drugs (i.e, increase PGE2 and decrease PGD2) has in the past been postulated to be the perfect treatment to regrow hair. I would urge all blog readers to listen to this encouraging audio segment on Setipiprant from an investor call earlier this year.

PRP and Hair Loss Updates

— An interesting article on Dr. Joseph Yaker in Texas using PRP along with stem cells derived from a donor’s placenta to treat hair loss.

— The renowned Dr. John Cole is planning to do a major study on the effectiveness of platelet-rich plasma (PRP) therapy. The PRP treatment will entail three sessions (once a month for three months) costing a total of $750, an absolute steal. Moreover, it seems like Dr. Cole will even refund that $750 if you show up for a follow-up session 6-12 months after the first set of injections. Dr. Cole will test many different treatment protocols, including using a variety of extracellular matrix (ECM) products and activation methods.

PRP is still fairly new when it comes to the hair loss world, with many significant differences in methodology and ingredients existing between different doctors and hair transplant surgeons. Such a study needed to be done a few years ago. If you do volunteer for this study, please make sure you know exactly what Dr. Cole will inject into your scalp. He is very well respected and unlikely to do anything even remotely risky, but when you are injecting something into your scalp, it is best to be very cautious.

And now on to medical items of interest:

— A new study finds that keeping PGE2 levels high in mice by reducing 15-PGDH promotes tissue regeneration. It seems like PGE2 has many benefits besides hair growth.

— A groundbreaking new $25 blood test called VirScan that can tell you every virus you have had. An average person has been exposed to 10 of the 206 known viruses that infect humans.

— An update on the patient who might get a full body transplant (always inaccurately referred to as a head transplant by the media).

— Since I already covered the above story several times this year, the one on a Chinese surgeon who has performed 1,000 head transplants in mice and plans to move on to monkeys next is more interesting. Albeit revolting and slightly discouraging since the mice usually only survived for minutes, with the record being 10 days.

The excellent WSJ article with a video on this requires a subscription. I did not realize the now obvious conclusion that a full body transplant would be revolutionary when it comes to most types of cancer treatment. However, even I do not foresee a successful long-lasting full body transplant in a human for many decades to come. Nevertheless, what an insane era we are living through.

Kythera Biopharmaceuticals, George Cotsarelis, Luis Garza, PGD2, Setipiprant

Setipiprant Global Rights Purchased by Kythera

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Update: October 2021 — Unfortunately, the clinical trials of Setipiprant for androgenetic alopecia saw no hair growth benefits. The trials were conducted by AbbVie (US), which purchased Allergan in 2020.

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

Setipiprant Rights Purchased by Kythera (now 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.

Setipiprant Trials

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

PGD2 has been in the news a lot in the hair loss world during the past several years. This is in large part due to Dr. Luis Garza’s work and excellent publicly available 2014 paper on the subject. And also due to the 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.