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It’s 2008; how did the various male contraceptive methods being studied fare during 2007? Here's a quick summary, with a focus on the methods already in clinical trials:
Male Hormonal Contraceptives
Multiple clinical trials on multiple formulations have now shown both high contraceptive efficacy and reliable reversibility. However, the mysterious double-digit non-response rate continues to puzzle researchers. New pill forms being developed at two startup companies show promise and should be more appealing than shots and implants. Most research is happening at university labs, as the last remaining major pharma players left the field in 2007.
Intra Vas Device, US design
Researchers are midway through the Phase I study of 82 men who received the implants last year. (The plugs block sperm like vasectomy but are hoped to be more reversible.) Preliminary results show time to infertility similar to vasectomy by traditional techniques (as opposed to the new gold standard vasectomy technique, fascial interposition, which results in a faster drop). The study has identified several simple changes which will make insertion much easier. Shepherd Medical is actively and successfully soliciting investors, and will ask the FDA to approve a larger study at 15-20 North American sites as soon as enough data are in, giving men in many more regions an opportunity to participate. The next study will begin to address the question everyone is asking: upon removal, how well would fertility come back ?
Intra Vas Device, Chinese filter-core design
Press reports, yet to be confirmed, cite testing in over 1,600 men in China with 100% success. The Male Contraception Coalition will be reporting more information on this method in the next few months, including newly translated clinical trial publications.
Testicular Ultrasound
Investigators are continuing to refine their equipment and techniques in small pilot studies. Once lab results align more closely with those reported in the original studies, they’ll begin the planned full-scale study in rats. If this respected team of researchers finds contraceptive effect, it would be a big boost for this method first reported to work in the 1970’s and 1980’s in rats, rabbits, monkeys, and 8 men.
Retinoic Acid Receptor Antagonists
Tests in mice found about 14 weeks of contraception from 7 days of treatment. Columbia University researchers are looking for funding to take work on this nonhormonal oral contraceptive to the next level – testing in primates. Such work will quickly run into seven figures. In the meantime, the researchers are pushing the duration of treatment to see how reliably fertility returns. The current experiments will test the effects of repeated doses over 3 months. One big advantage to this contraceptive: Significant safety work has already been done in humans, because the drug was originally developed for another purpose.
RISUG
Phase III clinical trial in India continues enrollment.
No news…
Tripterygium wilfordii derivatives, wet heat, artificial cryptorchidism, Dr. Joseph Hall ’s enzyme inhibitor approach, an Eppin immunocontraceptive, high-intensity focused ultrasound (HIFU) for permanent vas occlusion, and gossypol as a nonsurgical vasectomy alternative.
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Male contraception research has made great strides in the past year, with overwhelming evidence of public demand, several new studies started, and the September "Future of Male Contraception" conference cementing the new energy and enthusiasm. Where would we like to be a year from now? Here's Elaine Lissner of MCIP ’s wish list, what we'd like to be reporting to you at the end of 2008:
- Studies on the 5 unexplored Tripterygium wilfordii extracts underway. One extract of this readily-available Chinese herb did not work out, but researchers should get NIH funding to test the other five extracts. The parent compound is used in the treatment of autoimmune diseases and is known to have contraceptive effect; the goal is an extract that has contraceptive but not immune action. A small clinical study should also be initiated to confirm the contraceptive effect (as reported in the Chinese Journal of Andrology) and examine the safety of glycosides of T. wilfordii, another readily-available preparation.
- Progression of Shepherd Medical Company’s Intra Vas Device clinical trials to Phase II, allowing clinicians around North America to refer their patients who are interested in an alternative to vasectomy.
- Funding to test Columbia University researchers’ oral method in monkeys.
- After an extended period of fine-tuning equipment and techniques, researchers are set to announce in early 2009 that they have confirmed the contraceptive effect of 10 minutes of testicular ultrasound in rats. Given that previous work in rats, rabbits, monkeys, and men is now seen as valid, investigators are already talking with the FDA for guidance on the next step for testicular ultrasound — possibly a clinical trial with men planning vasectomy — upon successful results from the current study.
- FDA guidance on the next step for testicular ultrasound—possibly a clinical trial with men planning vasectomy — upon successful results from the current study.
- Foundation funding allowing the first India-US collaboration on RISUG: large-scale GMP manufacturing followed by a rabbit study. In addition, release by the Indian Council for Medical Research of results of the long-term follow-up study (based on interviews and exams of the several hundred men who have had RISUG 5 to 7 years), providing the first published data on RISUG's long-term effects in humans.
- Planning already underway for the next "Future of Male Contraception" conference, with organizers making sure there’s money for developing-country researchers to be there.
Kirsten Thompson, director of the IMCC, adds the following items:
- Continued development of testosterone formulations that can be taken in pill form (rather than as shots), and a better understanding of why some men don’t respond to hormonal contraception.
- Coordinated research & development grantmaking based on a transparent and cohesive prioritization process.
- A survey of North American doctors and family planning providers to understand their attitudes toward novel male contraceptives, so we can plan for training and distribution when new contraceptives become available.
These are just some of the advances we hope to be able to report at the end of 2008. By continuing to tell patients and colleagues about promising male contraceptive leads and by filling out our survey if you haven’t yet, you can play a part in making them happen!
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The ACQUIRE project has developed a new set of training modules for family planning providers who would like to add No-Scalpel Vasectomy (NSV) to their services. The curriculum has been revised and updated to reflect the latest research findings on NSV (the new gold standard in vasectomy procedures), as well as global expert opinion and field experience from many countries. This clinical training course presents all of the information that both trained vasectomists and their assistants need to be able to provide safe and effective NSV services.
Read more:
Trainer manual
Participant manual
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Is there a trend in decreasing sperm counts? Researchers in Scandinavia think so. The initial decline from average sperm counts above 100 million/ml in the 1940’s to 60-80 million/ml more recently is not likely to have caused significant infertility. They believe, however, that men in Northern Europe may soon cross a threshold into subfertility, a threshold they propose is at 40 million sperm per milliliter of semen. Forty percent of men in Denmark now have counts below this level. As a result, “ we must face the possibility of more infertile couples and lower fertility rates in the future.” The authors conclude that “if the hypothesis of fetal origin of these reproductive health problems is valid we may not see the full effect of preventive measures within the next 30 years, even if we knew how to instigate them now. We have no time to waste in our efforts to identify the causes of these health problems.”
Read more:
Adverse trends in male reproductive health: we may have reached a crucial 'tipping point'
Andersson AM, Jørgensen N, Main KM, Toppari J, Rajpert-De Meyts E, Leffers H, Juul A, Jensen TK, Skakkebæk NE.
Int J Androl. 2008 Jan 10 [Epub ahead of print]
PMID: 18194282
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Male contraception hits the humor column! "Unconfirmed Sources" presents a parody story on "Plan D," the supposed experimental male contraceptive mistakenly released by the manufacturer "Barred Pharmaceuticals." Women who gave it to their partners reported "an overall diminished interest in sex from their partners with an increase in their emotional attention span" and "no real adverse side effects such as sedation, and in fact, their partners appear to be more energetic and involved with completing household chores." Of course the real male contraceptives in development aim to work without changing hormone levels, leaving men and women to divvy up household chores without pharmaceutical intervention...
Experimental Plan D Released as Over the Counter by Mistake [parody]
Unconfirmed Sources, 8 January
Humorous column, with comments, by an Australian bloke on how he talked himself into a vasectomy after hearing lots of myths and having one false start. "The operation was as smooth as a gravy sandwich. As the hot laser deftly did its work, I found myself humming Jerry Lee Lewis's immortal lines: "Goodness, gracious, great balls of fire!"
Taming of the cue
The Sunday Times ( Perth ), 11 January
Dr. R.S. Sharma, Deputy Director General of the Indian Council of Medical Research, gives an update on the RISUG clinical trials process, mentioning that the current study has been extended to 10 centers in India.
Injectable male contraceptive trial enters phase III
Daily News and Analysis India, 25 January
Researchers in Australia are trying to design a radio-controlled vas device. You’ll likely be seeing a lot of this in the press, even though it is very preliminary work.
Radio-controlled sperm 'tap' turns off vasectomies
New Scientist, 28 January
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Editors
Elaine Lissner, Director of the Male Contraception Information Project (MCIP)
Email: info@NewMaleContraception.org
MCIP is entirely nonprofit and works in three areas: raising public awareness of promising nonhormonal male contraceptives, advocating increased and expedited government research, and serving as a resource for journalists who wish to write about the subject.
Kirsten Thompson, Director of the Male Contraception Coalition (MCC)
Email: info@MaleContraceptives.org
The Coalition’s objectives are to speed the development of new male contraceptives through increased legislative and institutional support, to raise funds for applied male contraception research and development, and to educate the public about the work of the research community.
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