HIV treatment – resistance
HIV can become resistant to the drugs used to treat it, and drug-resistant virus can be transmitted to others. About 10% of new HIV infections are with a strain of the virus that is resistant to at least one anti-HIV drug.
There have been some big improvements in HIV treatment in recent years.
New drugs have become available that involve a lower risk of resistance. Now research has shown that the transmission of HIV with resistance to two of these newer drugs is rare – the two drugs were T-20 (enfuvirtide, Fuzeon) and raltegravir (Isentress).
Between 2008 and 2010, doctors in Italy monitored 79 patients, who had been recently infected with HIV, for resistance.
Overall, 18% had resistant virus, but in almost all cases this involved resistance to older classes of anti-HIV drugs, especially non-nucleoside reverse transcriptase inhibitors (NNRTIs).
But none of the patients had HIV that was resistant to raltegravir, and only one patient was infected with virus that was resistant to T-20.
Taking your HIV treatment properly can reduce the risk of resistance. You can find out more about this in the NAM booklet, Adherence and resistance.
HIV treatment – bone loss
Like all medicines, the drugs used to treat HIV can cause side-effects, one of which is a thinning of the bones.
It has been thought that treatment with tenofovir (Viread, also in the combination pills Truvada and Atripla), or some proteases inhibitors are especially associated with this side-effect.
But a small Swiss study has cast new light on this issue.
It showed that patients who were taking HIV treatment had more bone loss than those who were not taking therapy.
However, there was no evidence that tenofovir or any individual class of antiretroviral was associated with a greater risk of bone loss. Instead, bone loss seemed to be a general side-effect of HIV treatment.
Bone metabolism should be monitored as a part of routine HIV care. This means that problems can be spotted early and appropriate treatment offered.
HIV treatment – changing treatment
HIV treatment is getting better all the time. The drugs used today are generally easy to take and usually cause only mild side-effects that often lessen or go away with time.
But some people still find it necessary to change their treatment because of side-effects, and a potential option is maraviroc (Celsentri). The drug is approved for patients with experience of HIV treatment as well as those who are starting therapy for the first time.
Maraviroc works by blocking a receptor on the surface of CD4 cells that HIV latches on to. This is called a CCR5 co-receptor.
However, maraviroc doesn’t work for patients whose cells have a different type of co-receptor called CXCR4. This is usually seen in people who are very ill with HIV, and in patients who have taken a lot of anti-HIV drugs in the past.
All patients should have a test to see which co-receptor their HIV uses before they start treatment with maraviroc.
But these tests only work if a person has a detectable viral load.
This means that the test won’t be of any use for people who are taking an otherwise successful combination of anti-HIV drugs, but who wish to switch to maraviroc because of side-effects.
Their study involved 37 patients who were taking a break from HIV treatment.
They monitored stored blood samples to see which co-receptor patients had before starting HIV treatment. The patients’ co-receptor status was checked again when they had a detectable viral load during their treatment breaks.
Only two patients experienced a change in their co-receptor.
The researchers therefore concluded that testing stored samples, and looking at a patient’s treatment history, will accurately show which co-receptor their virus uses even if they are taking successful HIV treatment.
HIV and hepatitis C
Approximately 9% of HIV-positive patients in the UK are co-infected with hepatitis C virus, a new study has shown.
Prevalence of hepatitis C was highest among injecting drug users (84%). This is not surprising as hepatitis C is transmitted through contact with blood.
Approximately 7% of HIV-positive gay men were co-infected with hepatitis C. It’s likely that most of these men were infected through sex, but the researchers also think that some gay men may have been infected through injecting drug use. The prevalence of hepatitis C in heterosexual men and women was low.
There was no evidence that co-infection with hepatitis C resulted in a poorer response to HIV treatment.
The research also showed that 80% of HIV-positive patients in the UK have been tested for hepatitis C at least once. Guidelines recommend that all patients should be tested for the virus, and people at risk of hepatitis C should have regular screening.
Treatment is available for hepatitis C, and the best results are seen if it is provided soon after a person is infected with the virus.
You can protect yourself and others from hepatitis C by using drugs safely.
Unprotected anal sex, group sex, drug use and fisting have all been associated with sexual transmission of the virus. Condoms for penetrative sex and gloves for fisting provide protection against hepatitis C. Sharing sex toys and lubricants may also be a risk factor.
Warning issued in US to HIV/hepatitis C patients who use injectable treatments
The Food and Drug Administration (FDA) in the US has issued a warning about four injectable drugs that are used by people with HIV and hepatitis C. The drugs are T-20, Pegysus, Viraferon Peg, and Intron A.
The warning concerns contamination of the alcohol swabs supplied with these medicines.
Microbial contamination of these swabs, or pads, has been discovered.
The manufacturer of T-20 and Pegysus has recommended that patients should stop using these pads immediately and throw any remaining stocks away.
MSD, the manufacturer of Viraferon Peg and Intron A, has issued the following advice to people currently using these injectable products in the United Kingdom:
“You may begin receiving packages of ViraferonPeg or IntronA that do not contain alcohol prep pads. In this case, please use alternate alcohol pads that are available for purchase at your local pharmacy or you can use sterile gauze pads in conjunction with bottled isopropyl alcohol instead of the Triad Group brand alcohol pads.”
The warning only concerns the pads – the FDA has stressed that there’s no concern about the safety or effectiveness of the medicines.