A SERM (fispemifene) increases testosterone but not sex drive

[Nelson Vergel]

Shares of San Diego-based Apricus Biosciences were crushed this morning after the biotech reported that its experimental testosterone-boosting drug had failed both the primary and secondary endpoints in a Phase IIb study among men with secondary hypogonadism and sexual dysfunction. And the setback raises some additional issues for the entire drug class.


Researchers noted that fispemifene at 450 mg did boost testosterone among the men in the study, but failed to improve erectile function or low libido, missing out on providing a clear clinical benefit--an urgent necessity in the wake of the FDA's increased vigilance on testosterone therapies. As a result, the biotech plans to bury the program and focus on other work.

Fispemifene is a once daily orally administered selective estrogen receptor modulator (SERM) in development for multiple urological conditions in men.

http://www.fiercebiotech.com/story/...osterone-drug-following-trial-flop/2016-03-28

Note: I suspect the same issue with this product:


The FDA sends the maker of enclomiphene back to drawing board

 

[PAUL-E]

That's very interesting to bad they most likely won't investigate into why that is. I think testosterone most likely plays more roles in the human body than we are even aware of.

 

[Dr Justin Saya MD]

Everyone should note they state "While we did see statistically meaningful changes in testosterone levels into the low normal ranges with fispemifene, the compound's ability to increase those levels sufficiently to demonstrate clinical benefit is limited, and may be an issue with the entire SERM class"...

When have testosterone levels in the "low normal ranges" EVER resulted in "clinical benefit"? Even frank TRT with levels in the "low normal" ranges typically fails to produce "clinical benefit".

Crazy with billions of dollars at stake in this market that they have such flaws in their studies and now are scrapping the entire development of the drug...they need more knowledgeable/experienced folks designing/running the studies (likely same problem with Repros).

 

[PAUL-E]

Everyone should note they state "While we did see statistically meaningful changes in testosterone levels into the low normal ranges with fispemifene, the compound's ability to increase those levels sufficiently to demonstrate clinical benefit is limited, and may be an issue with the entire SERM class"...

When have testosterone levels in the "low normal ranges" EVER resulted in "clinical benefit"? Even frank TRT with levels in the "low normal" ranges typically fails to produce "clinical benefit".

Crazy with billions of dollars at stake in this market that they have such flaws in their studies and now are scrapping the entire development of the drug...they need more knowledgeable/experienced folks designing/running the studies (likely same problem with Repros).

Yes everyone is different I was having issues back a few years ago when my total t was in the mid 300s even thought it's considered the "NORMAL'' range buy most GP's and I was in my 20's

 

[John O'Connor]

Interesting pharmacological effect. Do most estrogen blockers also act specifically at the level of the pituitary? I know testosterone is converted to estrogen, thus the common need for aromatase inhibitors, but didn't know blocking estrogen would cause testosterone to increase. If anyone can explain this, I'd love to understand it.

http://www.apricusbio.com/pipeline/fispemifene/
"Fispemifene acts in secondary hypogonadism by inhibiting the negative feedback of testosterone production via an estrogen-blocking effect at the level of the pituitary, resulting in increased testosterone production in the testes"

 

[John O'Connor]

Clomid acts at the hypothalamus: from Wikipedia: "Clomifene inhibits estrogen receptors in the hypothalamus, inhibiting negative feedback of estrogen on gonadotropin release, leading to up-regulation of the hypothalamic–pituitary–gonadal axis.[SUP]["

I need to read a biochemistry chapter on estrogen and the hypothalmic-pituitary-gonadal axis.

For those using Clomid - is it typically used by itself or with Testosterone and/or HCG?[/SUP]

 

[Nelson Vergel]

From my book

"Clomiphene citrate is a selective estrogen receptor (ER) modulator approved in 1967 for the treatment of female infertility. It should be noted that most of the data for clomiphene were obtained through studies conducted in women, and good studies with its use in men have yet to be conducted (there is a company setting up research studies to explore the use of clomiphene in men with hypogonadism induced by long term anabolic steroid use). Clomiphene citrate's mechanism of action is primarily as an “antiestrogen.” It occupies estrogen receptors and “deceives” the hypothalamus into sensing a low estrogen environment. This activity enhances the hypothalamus' release of GnRH, which impacts the HPGA by stimulating release of FSH and LH from the pituitary. Clomiphene citrate may provide an approach to hormone replacement that is more similar to the normal physiology of the HPGA compared with testosterone replacement therapy, and it may preserve fertility. However, several studies evaluating clomiphene citrate for the treatment of male infertility have produced mixed results. Further study will be needed to clarify the compound's potential utility in this indication.But can clomiphene improve sexual function in men without the co- current use of testosterone? To answer this question, Dr. Guay and his team
at the Center for Sexual Function in Peabody, Massachusetts, studied the effect of clomiphene citrate on primary hypogonadism (testicles themselves aren't producing enough testosterone) and erectile dysfunction in 272 men who have never used testosterone. Of these 272 trial participants, 228 completed a four-month regimen of clomiphene citrate dosed at 50 mg three times a week.

Mean age of these 173 men was 54.3 years. After four months of treatment, 75.1 percent of subjects reported improvement in erectile dysfunction including 38.7 percent who reported normal sexual function. The other 24.8 percent reported no change in erectile dysfunction. Serum LH and testosterone levels increased significantly compared with baseline values in all groups (responders, partial responders, and non-responders).

Importantly, clomiphene citrate did not result in supraphysiologic (higher than normal) levels of testosterone in this study, and testosterone levels were maintained within a normal range. Multivariate analysis revealed that age was the patient characteristic most predictive of positive or partial response to clomiphene citrate, with patients aged 55 years and younger more likely to respond compared with patients aged 56 years or older. Free testosterone blood levels were not reported, so it is difficult to attain why there was a difference in response in older men.

For dosing and a protocol that uses clomiphene, HCG and tamoxifen to help to normalize the HPGA after testosterone or anabolic use, please refer to the HPGA dysfunction section and in the Chapter 7 (interview with Dr. Michael Scally).
More studies are needed using clomiphene citrate alone or in combination with HCG and/or tamoxifen or anastrozole so that doctors feel more comfortable prescribing these compounds to help balance the HPGA.

Practical matters to keep in mind: Some men report experiencing mood changes and feel more emotional when using clomiphene citrate. I have not seen any data on Clomiphene's effects on estradiol levels, so it is unknown if this reported mood changes are due to higher estradiol. Clomiphene citrate can be quite expensive, although it can be found at lower prices at compounding pharmacies by prescription. Many doctors do not like to prescribe it due to the limited available data and the fact that it is not approved for men. Some doctors prescribe it off-label and patients pay for it out of their own pockets. It is not a controlled substance under the US Drug Enforcement Agency (DEA). Some men order it for personal use from websites of overseas companies at very low prices."

 

[John O'Connor]

Thanks Nelson - so much to learn and so grateful for ExcelMale as an amazing resource. I will be purchasing your book soon.

 

[bazooooka]

Nelson, what's your thoughts on TORE as a monotherapy?

Nelson, does your book talk about Toremifene; what's the research say for monotherapy for improved T and sexual function in middle aged men? Thank you.