Teenagers targeted by vaccine research

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Teenagers targeted by vaccine research Donald G. McNeil Jr. NYT NEW YORK The future of vaccines, infectious disease experts say, is teenagers. Parents are used to the idea of their babies getting up to 20 vaccinations by age 2 to prevent polio, measles, chickenpox and other diseases transmitted by coughing.But pharmaceutical companies are inventing new vaccines against diseases usually transmitted by sex, drug use, foreign travel or living in dormitories or barracks. Half a dozen are now in the long and tangled medico-regulatory pipeline between the petri dish and the pediatrician's syringe."Adolescent vaccines are the next wave," Michael Decker, vice president for scientific affairs at the vaccine subsidiary of the Aventis pharmaceutical giant, said recently at a conference on immunization policy. "All the manufacturers have them in the works."The vaccines offer new ways to fight incurable illnesses that can kill or make life miserable. But they do no good after a disease has been caught, and getting them to teenagers in time presents enormous medical, financial and psychological challenges."It's hard," said Anne Oplinger, a spokeswoman for the National Institute of Allergy and Infectious Diseases, which is sponsoring clinical trials of a herpes vaccine. "Parents will have to take their daughters in to pediatricians when they're little girls to get them protected against a sexually transmitted disease."Complicating the problem, teenagers rarely visit doctors unless they are sick. High schools, unlike kindergartens, are not used to excluding students who have not had all their shots."You can't expect a teenager to say: 'Hmmm, I think I'm going to become sexually active. I guess I'll go get vaccinated for whatever diseases there are, along with birth control and stuff,'" said Daniel Salmon, a vaccination expert at the Johns Hopkins School of Public Health.Vaccines are also relatively expensive. The price paid by public health programs for a typical set of childhood shots rose to $385 in 2001 from $10 in 1971, according to a recent University of Michigan Medical School study; private doctors charge more.The complexity of ingredients in new vaccines, the lengthy testing involved and the risk of lawsuits over rare side effects raise the price, as does the need to make a profit in what is, traditionally, a low-margin business for pharmaceutical companies.A new vaccine can take up to 12 years to develop and test, and then, unlike a drug, "you don't take it three times a day; you take it once and it's done," said Adel Mahmoud, president of the vaccines division of Merck. Prices have not yet been set for future vaccines, but a vaccination against meningococcal disease now costs up to $80, and flu vaccines can cost $35 or more.Insurers often pay for childhood vaccines because it is far cheaper to prevent polio and the possible complications of measles, mumps, rubella and so on than to treat them. But protocols have yet to be established for teenagers.Last November, Stanley Plotkin, the inventor of the rubella vaccine and a leading researcher on many others, made some predictions for the next 10 years in the Jordan Report, an annual survey of vaccine development by the National Institutes of Health.By 2012, he said, there will be new or better vaccines for a wide range of conditions.Asked about his projections last week, Plotkin chuckled and said, "Well, you do have to take predictions with a large grain of salt, but I do think the ones about adolescents will prove correct."Early tests of a vaccine against the 70 different papillomaviruses show it to be highly effective, he said. It is most important for girls to get it because only women get cervical cancer. But men can transmit the viruses, and also get genital warts.Herpes vaccines are also primarily aimed at girls. One now in its final testing stage is about 75 percent effective in girls, said Robert Belshe, director of the Center for Vaccine Development at St. Louis University. Mysteriously, it does not protect boys at all, "but there really may be something to anatomy here," Belshe said, adding, "The vagina has a lot of antibodies in it, while the skin of the penis does not." Genital herpes is passed by skin-to-skin contact, and he theorizes that antibodies in the blood pass out of the cervix to protect sexually active women. It is important to vaccinate young girls, he said, because many pick up the related herpes virus that causes cold sores in the mouth early - possibly from kissing relatives or from sucking on toys as infants. The vaccine is believed to protect against both types of herpes, but to be ineffective if a girl already has either."The younger you use it, the more likely you are to get a benefit," he said. Asked how willing parents in his trials were to have young girls inoculated against a sexual disease, he said, "We've had a lot of discussion with mothers and daughters, and vaccines that protect reproductive health resonate with them.""It's not so much about protecting against sexually transmitted infections," he went on, "as it is about making sure you won't get cervical cancer in 20 years, and about protecting babies."The New York Times