Drug Resistance

Viruses and other harmful organisms can become resistant to the drugs that are used to prevent or treat them. This can happen for a variety of reasons, including the use of suboptimal levels of a drug or the use of a drug when it is not needed. Microbicide researchers minimize the risk that HIV will become resistant to a particular microbicide by making sure that women who are infected with HIV do not use the study drug and that those who become infected with HIV during a trial discontinue use.