Category Archives: Dutasteride

GSK Publishes Japanese Dutasteride Hair Study Results

I previously wrote about dutasteride possibly being approved by the US FDA to treat hair loss in 2015.  In August 2014, GlaxoSmithKline (GSK) published 6-month interim results from a Japanese clinical study of 120 male patients with androgenetic alopecia taking 0.5 mg of dutasteride daily.  You can also download the findings by clicking on the Result Summary tab here and then clicking on the pdf link there.

It should be noted that all patients were Japanese and four patients withdrew from the trial.  Key findings:

  1. 81 percent of patients saw at least some increase in vertex hair count (10 percent saw a great increase, 33 percent saw a moderate increase).
  2. 71 percent of patients saw at least some increase in frontal hair count (8 percent saw a great increase, 32 percent saw a moderate increase).
  3. Only one patient saw a decrease in vertex hair count, and only one patient saw a decrease in frontal hair count.  It is not clear if this was the same patient.  Both saw only a slight decrease.
    (My note: For all intents and purposes, this implies that Dutasteride guarantees at the very least hair loss cessation after 6 months of use).
  4. 11 percent of patients reported erectile dysfunction as a side effect and slightly smaller percentages of patients reported decreased libido, ejaculation disorders and sexual dysfuntion.(My note: Since each patient can report more than one side effect, I am guessing that most of the 11 percent reporting erectile dysfunction also reported the other sexual side effects I listed above.  However, the end of the pdf states that 38 percent of patients had side effects, which I think is an error as they are ignoring multiple side effect reports).

For 6 months, I found the hair loss related results slightly better than expected, but the side effects slightly worse than expected.  I am assuming here that something like 15-20 percent of patients had side effects rather than 38 percent as reported, based on my assumption that multiple side effects on one person were reported individually (i.e., double, triple… counted) for some reason.

If 38 percent of patients really did get side effects, we will not see Dutasteride getting approved to treat hair loss in the US or Japan in my opinion.

Dutasteride works when Finasteride fails

An interesting study by South Korean scientists was recently published in “The International Journal of Dermatology” .  They took 35 balding people who did not see any improvement while on Finasteride 1 mg/day for 6 months. They then put those same people on Dutasteride 0.5 mg/day for 6 months.   31 of those patients completed the 6 months of treatment.  **Hopefully, the 4 who stopped treatment were just tired/bored/worried/paranoid, and did not stop due to experiencing significant side effects.

Over three-quarters of these 31 patients saw at least some increase in hair count.  Only 1 patient had a marked improvement, while 6 patients had a moderate improvement and 17 patients had a slight improvement.  The remaining 7 patients did not see any improvement or worsening.   “Side effects included transient sexual dysfunction in six patients (17.1%)”.

Link to study summary –>  Dutasteride works when Finasteride fails.