Pill may cut HIV risk as much as 99 percent

Pill may cut HIV risk as much as 99 percent

Daily use of a pill ap­proved to pro­tect against HIV in­fec­tion cuts a man's risk of get­ting the vi­rus by 99 per­cent, a new study in­di­cates.

The re­search al­so of­fers the first ev­i­dence that even im­pe­r­fect ad­her­ence to the treat­ment reg­i­men can pro­vide a big re­duc­tion in the risk of ac­quir­ing the vi­rus, which causes AIDS. Par­ti­ci­pants in the re­search were found to be able to cut their HIV in­fec­tion risk by 76 pe­r­cent merely by tak­ing two doses a week.

The stu­dy, pub­lished in the Sept. 12 on­line is­sue of the re­search jour­nal Sci­ence Transla­t­ional Med­i­cine, ex­am­ines the ef­fec­tive­ness of a FDA-ap­proved drug known as teno­fovir diso­proxil fu­marate (brand name Tru­vada).

The re­search builds on a 2010 study by Rob­ert Grant at the Uni­vers­ity of Cal­i­for­nia, San Fran­cis­co and the Glad­stone In­sti­tute in San Fran­cis­co, along with col­leagues. The team found that Tru­vada-which had been used for years to treat HIV-positive pa­tients-could al­so pre­vent new in­fec­tions in peo­ple likely to come in con­tact with the vi­rus.


But ques­tions about the drug's real-world ef­fec­tive­ness re­mained-in par­ticu­lar con­cern­ing the is­sue of ad­her­ence to a reg­i­men of a pill a day. “There was con­cern that the pro­tective ef­fect of Tru­vada was frag­ile, and that in­di­vid­u­als tak­ing the drug would need to ad­here pe­r­fectly to daily reg­i­men for it to work,” said Grant. “This new study sug­gests that Tru­vada can help block the vi­rus even if the pe­r­son on a daily reg­i­men does­n't al­ways ad­here pe­r­fectly.”

The study ex­am­ined the risk of HIV ac­qui­si­tion in men who have sex with men. Par­ti­ci­pants dif­fer­ent doses of the drug. Men came in­to a clin­ic eve­ry day and were giv­en ei­ther two pills per week, four pills per week or se­ven pills per week. The re­search­ers then com­pared drug con­centra­t­ions from their study to drug con­centra­t­ions from a pre­vi­ous stu­dy.

The re­search team es­ti­mates that par­ti­ci­pants could re­duce their risk of HIV by 76 pe­r­cent tak­ing two doses per week, 96 pe­r­cent by tak­ing four doses per week, and 99 pe­r­cent by tak­ing se­ven doses per week.

The tim­ing of the dos­ing rel­a­tive to sex­u­al in­ter­course likely mat­ters, based on re­search done in non-human pri­ma­tes, al­though this could not be in­ves­t­i­gated in de­tail in peo­ple, the re­search­ers added. High­er drug con­centra­t­ions and more fre­quent use may be re­quired for wom­en be­cause the drugs are not con­centrated as much in the fe­male gen­i­tal tract, the au­thors not­ed.

“Pa­tients should still take one pill a day to achieve the best re­sults, and we en­cour­age peo­ple to ex­plore mul­ti­ple meth­ods to pre­vent HIV-such as reg­u­lar con­dom use, early treat­ment of HIV in­fec­tion in part­ners, good com­mu­nica­t­ion and male cir­cum­ci­sion,” Grant said. “We hope that our find­ings lead to more ef­fective use of pre­vention tools that fi­nally squash the HIV/AIDS epi­dem­ic.”


Source : http://www.world-science.net

Leave a comment