New Birth Control Methods May Reduce Cancer and Infection Risk
Two separate research efforts—one focused on preventing transmission of sexual infections and the other on treating cancer —may ultimately lead to much-needed new contraceptive methods. The first is a vaginal ring containing microbicides designed to prevent transmission of HIV which, if combined with hormones, could become a method of dual protection. The second is a discovery that could lead to a non-hormonal oral contraceptive pill for men. Each of these advancements has the potential to create more contraceptive options; right now, condoms are the only method available that prevent both pregnancy and disease, and the only reversible method that can be used by men.
It takes a long time, however, for a new contraceptive method to make it through the pipeline to the pharmacy shelves and I feel compelled to mention that, in the meantime, there is no excuse for people not to be using the ones we already have. I will get to that lecture in a minute. Let’s start with the science.
A Microbial Ring Could Become A New Form of Dual Protection
Researchers at the Population Council, an international non-profit research organization based in New York City, hold the patent on something they call MIV-150. Though it sounds like a spy organization, it is actually an allosteric enzyme inhibitor. As Tom Zydowski, one of the senior scientists on the project, explained it: “[MIV-150] essentially blocks HIV replication…It doesn’t change the shape of HIV, but it changes the shape of a key enzyme that HIV use to reproduce.”
MIV-150 was initially tested in the early 2000s in oral form but was not effective because it was poorly absorbed by the blood stream and cleared from the blood very quickly. More recent studies delivered this microbicide in gel form and found that when put directly into the vagina it was effective because it is absorbs into the tissues and “…latches on to some of the virus before it attacks the cells.” This week, the same team of researchers released a study showing that MIV-150 can be delivered into the vagina using a vaginal ring similar to those that are currently used to deliver hormones for pregnancy prevention.
Scientist inserted the rings into macaques and then exposed them to SHIV (a combination of HIV and the monkey version of it called SIV) either 24 hours or two weeks later. To add to the experiment they removed the rings in some monkeys just before they were exposed to the virus and in other monkeys just after. Some monkeys were given rings with active ingredients while others were given placebos. Only two of the 17 monkeys with the active ring became infected compared to 11 of the 16 monkeys who were given the placebo. The researchers concluded that overall the rings provided 83 percent protection from HIV transmission. They found that it didn’t matter when the ring was inserted but it did have to be in place at the time of exposure in order to work; four of the seven monkeys who had their ring removed right before they were exposed to the virus became infected.
This research is great news for HIV prevention and the researchers hope it will have additional commercial uses as well. Initially, they are developing a ring that has both MIV-150 and zinc acetate because this combination has been found to be more effective and may make it harder for the virus to mutate and become resistant. Moreover, by adding zinc acetate the rings have the potential to also prevent Herpes. But that’s not all folks as Zydowsky told Fox News:
“So maybe we also throw in something to tackle HPV—a huge medical need throughout the world. One scenario would be to get maximum bang for the buck; if we can get a ring to tackle multiple STIs that would be a great thing.”
Of course, Zydowski agrees that what would be even better would be a ring that could tackle multiple STIs and unintended pregnancy. And that is the ultimate goal—providing both HIV-prevention and contraception in a single method, something that as of now only condoms (and strict abstinence) can provide.
A Male Birth Control Pill
As of now, condoms are also the only reversible method available to men who want to take on the task of preventing pregnancy. Of course, men can also have a vasectomy, a procedure in which the vas deferentia are severed to prevent sperm from being released during ejaculation. This procedure, however, is meant to be permanent.
For years we’ve heard tales of the imminent arrival of a male birth control pill—one that would inhibit sperm production in much the same way that oral contraception inhibits ovulation. A number of researchers have attempted this using testosterone, a hormone that can interrupt the feedback loop that signals sperm production, and more recently researchers have added progestin, a synthetic version of the hormone progesterone, that can amplify these effects. These substances have been combined in various forms such as pills, shots, and implants but trials of these drugs showed that they didn’t always limit fertility and they often had unwanted side effects such as acne, high cholesterol, and breast enlargement. (This summer, the Population Council—the same organization developing the vaginal ring —has found initial success with a gel version of the two hormones.)
The most recent discovery that could lead to a male birth control pill was actually made in a cancer research lab. A team at Dana-Farber Cancer Institute developed a new molecule that they name JQ1 (after a chemist in the lab). The molecule was meant to:
“affect a structure on tumor cells called BRD4, which seems to make cells remember they are cancer. Just like a key fits into a lock, JQ1 can slide up against BRD4 and inactivate it, making the cells “forget” to be tumors.”
As part of their efforts to test whether the molecule has any unintended effects on health cells in the body, the team looked for genes similar to BRD4. It found a protein in the testes known as BRDT that is critical for sperm production. As James Bradner, the lead researcher and author of a new study in the journal Cell, explained:
“We wondered whether JQ1 would enter the testicle, inhibit BRDT and cause the testicles to forget how to make sperm.”
In order to test this theory, the team collaborated with fertility researchers at Baylor College of Medicine. The fertility experts already knew that mice without the BRDT protein were infertile but were eager to determine whether inhibiting BRDT would have the same effect. It did. Mice who were given JQ1 became infertile and this infertility was reversible —once they came off the drug the mice were able to father healthy baby mice. Trials in people are years off but the fertility experts were able to determine that JQ1 did inactivate the human version of the BRDT protein.
In the Meantime – Condoms
There is a lot more research to be done before anyone can hand her boyfriend a package of pills and say “Honey, it’s your turn.” As one fertility expert put it:
“We are probably not talking about something that is going to be available in the next two years or even five. But this research represents a new biologic approach and it is certainly promising.”
The same thing can be said of the vaginal ring with microbicides and contraception—the Population Council suggested that the initial consumer products from this researcher were probably five to seven years off.
But that doesn’t mean that anyone has the excuse to just throw up their hands and take a chance. We have really good pregnancy and disease prevention options already—and we even have one that does both.
As my husband, the computer scientist, said when friends told us they weren’t really trying to get pregnant, they just weren’t using anything right now: “This is binary—either you are using contraception or you are trying to get pregnant.” Anyone who is sexually active and isn’t actively trying to get pregnant should be using a method of birth control (with the possible exception of those who really, really know they are not fertile).
There are many viable options of contraception. The pill, which celebrated a birthday recently, has spawned numerous forms of hormonal birth control from the ring to the shot to implants. Women who don’t like any of those options (maybe you can’t swallow pills or faint at the sight of a needle) can consider an IUD (now also called Intrauterine Contraception or IUC) which have a bad rap from the seventies but are now considered safe and effective even for women who have not yet had children and adolescent women. One of the available IUDs uses hormones and the other relies on copper so women who don’t want to use hormones (or can’t because of medical conditions such as high blood pressure) have an option there too.
There are other contraceptive methods available too (remember the diaphragm) but I want to take about our old friend the condom. Condoms do what the methods in the birth control pipe line are striving for—they prevent both pregnancy and STDs and they allow men to take on the responsibility of prevention and they’ve been doing it, in one form or another, for over 400 years.
Condoms get a bad rap for ruining the moment, smelling like band-aids, and reducing pleasure. I get that but I would suggest that you all give them another shot. They now come in all shapes and sizes and textures, no longer smell bad, and come with funky lubricants that do things like warm or tingle or both. Some even come packaged with a vibrating ring for extra fun.
But most importantly, they are available right now and they work to prevent unintended pregnancy and STDs—two things we have too much of these days.