The addition of Selzentry (maraviroc) and Isentress (raltegravir) to a standard triple drug antiretroviral cocktail rapidly suppresses HIV viral load in semen and significantly reduces the likelihood of intermittent, low level shedding of the virus in seminal fluid, aidsmap reports. Researchers published their findings in the online edition of The Journal of Infectious Diseases of this study of 13 gay men who began this intensified therapy and 25 controls who took a standard triple-drug regimen of antiretrovirals (ARVs). None of the participants had a sexually transmitted infection (STI), which has been shown to cause viral shedding in semen.

After recent studies have shown that suppressing viral load drastically reduces the likelihood of transmissions, other research has identified individuals who maintain an undetectable viral load in their blood, but who still experience isolated HIV shedding (IHS) in their semen, raising the possibility that they still may be intermittently infectious.  There have indeed been isolated reports of such transmissions.

Those taking the intensive therapy experienced more rapid viral suppression in their semen. IHS was found in more than one clinic visit in two participants (15 percent) on intensive therapy compared with 12 of the controls (48 percent).

After one of the participants maintained an undetectable viral load in his blood but a detectable seminal viral load for 14 months after beginning intensified treatment, the investigators observed another cohort to find if there was viral shedding in men taking long-term therapy. They examined blood and semen samples from 26 men who had been on long-term standard ARVs, all of whom had no STIs and an undetectable viral load in the blood.  

Among those in this group taking ARVs for less than six months, about half had intermittently detectable virus in their semen. Meanwhile, only 20 percent of those taking therapy for one to three years had detectable seminal virus; and none of those on treatment for more than three years did.

To read the aidsmap story, click here

To read the study abstract, click here