The Religious Consultation
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Kansas City Star, June 20, 2005 Nonhormanal Contraceptive
For Men Sought Condoms are inconvenient. Vasectomies are too permanent. So what’s a guy to do if he wants to avoid paternity? Researchers at the University of Kansas hope to offer men an alternative that has been available to women for decades — a pill that temporarily switches off their fertility. With a $7.9 million contract from the National Institutes of Health, a team of scientists will use a high-tech lab on the university’s Lawrence campus to test about a half-million chemical compounds to find promising candidates for a male contraceptive pill. The goal is a pill that men would take weekly or monthly. It would be virtually 100 percent effective and have no hazardous side effects. “I think some couples would like to have that option,” said Gunda Georg, a KU chemist and leader of the research project. “There’s been a shift in attitude. Some men would like to share more in that responsibility.” KU already has applied for a patent on a compound that the research team tested successfully on animals. Under the contract with the National Institutes of Health, the team hopes to discover a half-dozen more. Finding the right compounds, setting their dosages and making sure they are safe will take at least five years before clinical trials on men could be considered. But men — and women — have waited for a male pill for a long time. While there have been innovations in female contraception since the birth control pill was popularized in the 1960s, men have had to rely on the same two choices — condoms or sterilization — for more than a century. “Half of the population has been ignored,” said Joseph Tash, a reproductive biologist at the University of Kansas School of Medicine. Meanwhile, the female half of the population has taken on most birth control duties. Only 27 percent of women who practice contraception rely on their partners to use condoms or have vasectomies, according to data from the Alan Guttmacher Institute. But interest in creating more options for men has been growing, stimulated by some women’s hopes that men take more responsibility for birth control and the needs of countries such as China and India to control population. A large-scale test of a hormone-based male contraceptive is under way in China. Last year, two large pharmaceutical companies, Schering AG and Organon, announced they would test another hormone-based contraceptive on men at sites throughout Europe. Like the female pill, these male contraceptives manipulate sex-hormone levels to affect fertility. For men, that can be done with large injections of a male hormone similar to testosterone or with a combination of testosterone and a female hormone. Preliminary studies have shown that this kind of hormonal contraception is effective and that the men regain their fertility after several months, said Douglas Colvard, associate director of Conrad, a nonprofit organization at Eastern Virginia Medical School that promotes research on reproductive health. But testosterone injections raise health concerns such as elevating cholesterol levels and promoting cancer growth. “There’s the potential of stimulating a prostate cancer that’s already there,” Colvard said. The KU researchers are taking a nonhormonal approach. They are looking for chemicals that can disable a handful of enzymes that scientists have identified as critical to male fertility. Some of these enzymes are involved in the development of sperm in the testes; others enable sperm to swim to an egg. Based on computer programs and “experience and intuition,” the KU researchers have selected more than 100,000 compounds that might work, Georg said. The National Institutes of Health is giving KU its list of compounds, which will bring the total to about 500,000. Testing that many compounds for their effects on as many as eight enzymes would overwhelm a chemist in a conventional laboratory. But KU is one of a few universities with a robotic laboratory called a high throughput screening center. The laboratory can test thousands of chemicals at a time. After Georg winnows the number of compounds, the KU researchers will use other technology to scrutinize them at the molecular level to see how they bind to the enzymes. Georg might tinker with the molecules to make the compounds more effective. The best compounds then will go to the KU School of Medicine, where Tash will test them on mice or rats. He will see whether the compounds are effective, whether they are safe and whether the rodents regain fertility after they stop receiving them. “Obviously, the goal is 100 percent effectiveness,” Tash said. “The female pill is 95 to 99 percent effective. We hope to at least meet that level.” The researchers also seek a compound that would be as safe as the female pill. “The bar has been raised very high for a male contraceptive compound,” Tash said. In its work under a previous contract for the National Institutes of Health, the KU team identified a compound they named Gamendazole that made all the rats that received it infertile. However, only about 65 percent of the rats regained fertility afterward, a sign that the dose may have been too high. The researchers hope to arrange more animal tests on the compound. Any male contraceptive pill that is developed probably would have to be taken for an extended time to be effective, the researchers said. If a male pill were to go on the market, would men use it? Georg said she has heard that question whenever she tells people about her research. Men ask whether there would be wide acceptance of the pill by members of their sex. “When I talk to women, they ask, ‘Can I trust my partner to take it? Is he reliable enough?’” Georg said. “I think women are used to taking a lot of responsibility, and they’d have to give up some of that responsibility and trust someone else.” First glance
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