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ü Ll* A NEW PLANNING TOOL TO SLOW GROWTH

A safe, long-lasting, and reversible vaccine from six monthz to two years. Theoretically, 821 cycles developed in is poised to revolution- without contraception in different wome” would bave resulted in 250 to 300 . ize family planning. “We bave passed a” important milestone and that is to In New Delhi, India, a group of young wome” are among confirm the vaccine works,” says Dr Talwar. “‘Ibis is the the volunteers working to slow the advance of world popu- first time we’ve see” a vaccine that ca” lation growth. These women - teachen, nurses, and secre- prevent in humans.” taries - bave volunteered at two hospitals to participate in Despite this success, however, it Will be some time before tdals of a revolutionary birth contra1 vaccine. The women the vaccine is ready for the public. Vaccines for use in are between the ages of 20 and 36 and are of proven ferti- healthy people take a long time to be approved. “My hope ity, having completed their with at least two chil- is that before the decade ends it Will be available for public dren. Tbis group is proving that a shot in the ann with 300 use,” says Dr Talwar. micrograms of vaccine is a.” ideal contraceptive and one Clear advantages make the vaccine a” appealing alterna- which could be part of the solution to check the world’s tive to other family planning methods. It is reversible and it spiralling . lasts for one year. Most importantly, it does “ot disturb a The vaccine is the result of research begun in 1975 by woman’s . The vaccine dces not stop ovulation Dr Gursaran Talwar, Director of India’s prestigious National or alter the mensuual cycle. It avoids having to take a drug Institute of Immunology. IDRC has given Dr Talwar every day, as in the case of the birth control pill, or under- CAD$4.5 million for research “ver 17 years. He also going a” operation and experiencing the irregular bleeding receives funds from the . associated with IUDs. Eve” “ew devices such as Norplant, The vaccine works by “convincing” a woman’s body that a steroid pack implanted in a woman’s arm, cause irregular a11is unchanged when, in fact, a” egg has been fertilized. bleeding. After conception occurs, a woman produces a hormone Other characteristics make the vaccine particularly appro- called human chorionic gonadotrophin (hCG) that helps to priate for use in the developing world. It requires neither prepare the uterus for pregnancy. The prototype vaccine, the logistics “or the facilities needed to administer conven- made from hCG coupled to a biochemical carrier, neutral- tional types of birth conuol. It is also less intrusive, a poten- izes hCG by stimulating antibodies against the hormone. tially important factor in countries that bave cultural taboos Without hCG the embryo Can”ot anchor in the uterus, mak- against contraception. ing pregnancy impossible. The biochemical carrier makes Dr Don de Savigny, a program officer with IDRC’s the hCG immunologically visible to women’s immune Sciences Division, says the vaccine gives women a subtle system. way of at least spacing their births if “ot reducing the bur- “What you’re bascially doing is interpreting the signal that den placed on them by tradition and culture. “Ninety-nine tells the mom’s body to set up the whole uterine environ- percent of global maternal deaths occur in developing ment for pregnancy,” says Dr Talwar. “And if that [signal] countries. This vaccine an help alleviate the problem of doesn’t happe”, then you’re “a going to get a pregnancy.” insufficient spacing as one of the reasons.” In addition, In the vaccin& arototvce version, immunization begins wome” with many children close in age cannot give the with a series of thiee tare and attention each injections given at sut- requiws. week intervals. Af%erthe Dr Talwar empha- last shot, the woman is sizes that the vaccine is protected for a year. If “ot an anti-conceptive. she wants continued The hormone interven- protection, all that is tion acts after con- needed for the next ception, but pria to year is a single booster. embryo implantation If the woman wants to and txfore pregnancy bave a , she just cari be established. has to stop the injec- Eve” without the vac- tiqns and the hormone cine fertilization takes Will no longer be place a11the time in the neutralized. body without a preg- The latest clinical nancy rang place. studies of the vaccine “Nearly 75 percent resulted in only one of embryos are “or- pregnancy in 88 wome” mally lest at this stage. observed over 821 men- The vaccine simply sttual cycles. Tbe time increases this inci- _ . each woma” has been A newiy deueloped vaccine ho1d.sthepmmise 01 as@ yet dence to “car 100 on the vaccine varies unobt~ivefamilyplanning metbod. percent.”

16 IDRC Report~,January 1993 ‘Ihe vaccine’s use Will not be limited to developing coun- tries. “Many people want alternatives to current methods of A MALE VACCINE contraception. Human is a universal phenom- enon. There is no dividing line between North and South,” says Dr Talwar. India’s population explosion is exacerbated by It is no surprise, however, that the vaccine was devel- Hindu religious beliefs preventing the slaughter oped in India. With a rapidly increasing population of 876 of cattle. As a result, people compete for precious million, the government has placed a high priority on find- space with 297 million cows. Indian researcher ing a safe, easy-w-use, and effective method of birth con- Dr Gursaran Talwar developed a vaccine for trol. Current rates of growth predict India’s population Will bulls rendering their free of sperrn. The exceed that of - currently the world’s most popu- vaccine leaves the bull’s intact and is irre- lous country - within six decades. India’s objective is to versible. Possible spin-offs did not go unnoticed. attain by the year 2050 with a pop- A human version of such a vaccine could be ulation of 1.3 billion. the overdue answer for a long lasting male contra- In 1950, India was the first country to launch a family ceptive. Dr Talwar is developing a reversible con- planning program. Since then, India has acquired a reputa- traceptive made from a purified extract of the tion for its innovative ideas and for providing a testing neem tree called ‘praneem’. ground for new metbods of birth control. The vaccine, if Like the vaccine for bulls the vaccine for men approved, Will become a cornerstone in India’s goal of renders semen free of sperm. It does not disturb establishing the two-child family. the male libido or hormone levels and has resulted in no .

Although the vaccine’s success is evident, not everyone was convinced of its feasibility. Dr Talwar vividly describes the disbelief and skepticism that greeted his proposa1 in the early 1970s. “People felt that it was a fantasy. Vaccines were traditionally made for diseases, pestilence, viruses Through a11this, Dr Talwar credits IDRC with making his and bacteria - not birth control.” If researchers did not dis- research possible. “IDRC had the courage to pick up this miss the concept as a fantasy, they said it would not be safe venture,” he says. The Centre’s continued support since or reversible and that it would weaken the immune system. 1974 allowed Dr Talwar to obtain results which attracted TO refute these claims, Dr Talwar and his team subjected the attention of other groups. the vaccine to long, exhaustive toxicology studies and UNFINLSHED BUSINESS numerous clinical trials on animais before moving on to Dr Talwar is currently working on a compatible, safe 2nd human testing. The vaccine tri& also undenvent ethical effective method of birth control to protect women during reviews to ensure that the vaccine is reversible, non-toxic, the three month period when they are receiving the shots. and not a barrier to ovulation or menstruation. Indepen- At present, women in the tria1 are using IUDs or barrier dent studies bave confirmed Dr Talwar’s results. The Inter- meihods. national Committee for Contraceptive Research of the The purified extract of the neem tree is where Dr Talwar in New York, has conducted its own emecs to fïnd his solution. Called praneem, the substance toxicology studies on the vaccine in Brazil, Chile, Finland, h& prevented pregnancy in rats and monkeys for three and Sweden. months after being injected into the uteruus. Like the “For a scientist in a to make an ori@- vaccine, praneem dces net interfere with ovulation or na1 contribution, he OI she has to work five times barder,” menstruation. says Dr Talwar. IDRC has been able to foster North-South relations in this Indeed, some of the best scientific research institutions in area. In Canada, researchers at the University of Alberta are the world are in India, says Dr de Savigny. “Talwar’s collaborating on the neem studies to establish why and National Institute of Immunology is a world class institu- how the neem oil acts as a contraceptive. tion. Immunologists corne from a11over the world to work Another problem to be solved is how to administer the and study there.” In fact, birth control vaccines being devel- birth contra1 vaccine. Work is under way to create a deliv- oped in Ausualia and the United States are not as advanced ery system SO tbat women only bave to visit a family plan- as Dr Talwar’s vaccine. ning service once instead of three times. A biodegradable

IDRC Repens, January 1993 FROM PLANT TO POISON

implant wbich contains and secretes the necessary dosage for one year is ish and shrimp farmers throughout the world stand to being designed. Dr Talwar is also F working on a version of the vaccine profit from the discovery of an environmentally friendly that Will last two years. and cheap flsh poison (piscicide) to be used in the battle A.5with a11vaccines, there is a per- against unwanted predators. centage of the population that will ‘RE poison, called Swimtop, is the product of a seven-year research effort not produce enough antibodies when involving scient& from Chiang Mai University and the Prince of Songkla Univer- immunized. Accordingly, Dr Talwar is sity in Thailand and the University of British Columbia (IJBC) and the University developing an inexpensive, finger- of Ottawa in Canada. IDRC funded the project. prick test which will indicate whetber a woman is making enough anti- Natural predators, such as eels, mullet, sea bass, and tilapia, cari account for bodies. up to 40% of the losses in the commercial fish and shrimp harvest in Thailand. Producers bat& this problem by using cyanide - a poison that cari bave a seri- Once these technical problems are ou impact on all organisms in the food chai”, including humans. Many fish and solved, other questions remain. The shrimp farmers also use tea seed cake, which is the traditional means of control- introduction of such a revolutionary ling predators in Thai aquaculture. concept in family planning opens up a whole new arena of socio-cultural About CAD$2 million worth of tea seed cake is used annually in Thailand. and issues. Most of it is imported from China due to insufficient local production. In the cultivation of commercial ta, the plant’s terminal shoots are tut off SOthat Tbe vaccine’s impressive resultz so flowers and fruits are unable to develop. This practice means that there is not far are an encouragement to a11those enough tea seed in Thailand to use as an aquacultural piscicide. working to give women better control of their reproductive capacities, but as “Our goal was to find an ecologically acceptable alternative to tea seed and Dr Talwar states, although “the light is also one that vas in good supply,” says Prof Pichaet Wiriyachitra, a professor of green, there is still a lot more to do chemistry at the Research Centre of Natural Products at Chiang Mai University before we reach the end.” and tix project leader. Dr Neil Towers, a botanist at UBC, assisted Thai scientists in the collection and Peter Newton in Ottawa screening of plant species. More than 250 species were initially tested to assess their potential use as tish poison. Many were highly toxic to praiatory fish but were mled out beause they were in short supply. Some proved SOpoisonous that they were unsafe to handle. Scientists carried out the testing in Thailand and at UBC.

. F-3 Dr GursaranTalwar il National Institute of c - Immunology JNU Campus New Delhi 110067 India In an effort topmwne Ihailand’s comnercialf~b andshrtmp hawest, Tel. 662608 compoundsfmm a shmb ca&dMaesea ramentacea are ured to kil1 unwanted Fax: 9111-6862125 predatmyf%sh- witbout harming othe?‘organis?r~~ in tbefood cbain.