Nelfinavir (Viracept) recalled due to contamination

The protease inhibitor, nelfinavir (Viracept) has been recalled in the UK and Europe because some batches of the drug became accidentally contaminated during manufacture by large amounts of a chemical linked with cancer. 

The recall affects all batches of the drug, and anybody in the UK and Europe who is taking nelfinavir must contact their HIV clinic immediately so they can be offered an alternative treatment. The recall does not affect nelfinavir in the US, Canada and Japan.

It is thought that contamination occurred in late 2006. There were six reports from Spain and France of the drug having a ‘foul odour’.

Few people in the UK take nelfinavir. It is less powerful than the newer ritonavir-boosted protease inhibitors. It is relatively easy for HIV to become resistant to nelfinavir if a person does not take at least 95% of their doses at the right time and in the right way. However, a small number of people have been successfully taking nelfinavir for years. It is known to be a safe drug (its most significant side-effects being diarrhoea and an increase in blood fats) and is used in pregnancy and for people who need emergency post-exposure prophylaxis (PEP) after potential exposure to HIV.

HIV and hepatitis

Thanks to potent anti-HIV therapy, many people with HIV are able to live much longer and healthier lives. Indeed, doctors are now so optimistic about the effectiveness and safety of currently available anti-HIV drugs that they are hopeful that people with HIV will be able to live a more or less normal lifespan. 

But some people with HIV do still become ill and even die. The causes of illness and death for people with HIV have changed since effective anti-HIV treatment became available and traditional AIDS-defining illness now account for only a small proportion of illness and mortality seen in people with HIV.

One of the main reasons why people with HIV now become unwell or even die is liver disease. This is because many people with HIV are also infected with hepatitis B or hepatitis C. The life expectancy for HIV-positive people who have long-term coinfection with either (or both) of these viruses is somewhat less than people who only have HIV.

Doctors are doing a lot of work to try and see how best to care for people coinfected with HIV and hepatitis, and there was an important meeting of experts from around the world last week where some of the latest research findings were presented.

Treatment for hepatitis C – treatment during ‘acute’ phase has high success rate

Treatment is available for hepatitis C, and unlike anti-HIV therapy, treatment for hepatitis C can cure a person of hepatitis C infection. But anti-hepatitis C therapy doesn’t work as well in people who have HIV as well as hepatitis C, particularly if they have been infected with hepatitis C for a long time (chronic infection).

Much better results are seen when a person with HIV receives anti-hepatitis C treatment soon after they contracted hepatitis C. Doctors call this treatment for acute hepatitis C.

A new study conducted by doctors from the UK, France and Germany has found that almost two-thirds of gay men who receive treatment for acute hepatitis C are cured. This compares to a cure rate of 33% or less for chronic hepatitis C infection.

The effectiveness of hepatitis C therapy depends on the strain – or genotype – of hepatitis C. Genotypes 1 and 4 are the hardest-to-treat and, unfortunately, these genotypes are the most common ones in the UK. But doctors reported that gay men with these genotypes who received treatment during the acute phase had a cure rate of 60% - not much worse than the 64% seen overall.

It is recommended that people with HIV and hepatitis C should receive treatment with two drugs – pegylated-interferon and ribavirin. Both of these drugs can cause side-effects. Doctors reported that 13% of people experienced depression caused by pegylated-interferon and 10% were found to have a blood disorder, such as anaemia (a shortage of red blood cells), which is a recognised side-effect of ribavirin.

There is still some uncertainty about the best duration of anti-hepatitis C treatment, but doctors from the UK, France and Germany found that the best results were seen in people who received at least six months of treatment. It is recommended that people with the easier-to-treat strains of hepatitis C (genotypes 2 and 3) receive 24 weeks of treatment, and those with the harder-to-treat genotypes 1 and 4 receive 48 weeks of treatment.

Treatment for hepatitis C – many declining treatment

Although treatment for acute hepatitis C infection has the best chance of success in people with HIV, a study from London has found that only 25% of those people with HIV recently infected with hepatitis C are accepting hepatitis C treatment. Researchers found that people were often fearful of the side-effects of hepatitis C treatment and were waiting to start treatment until better anti-hepatitis C drugs became available. Drugs such as hepatitis C protease inhibitors are in development, but it will still be years before they are readily available. However, they appear to produce the best results when used with pegylated-interferon, and it is often the side-effects of this drug that people fear most.

Treatment for hepatitis C – interactions between HIV drug and hepatitis C drug

Medicines can interact with each other. Interactions can mean that medicines don’t work properly or cause unusual side-effects. It is therefore very important to make sure that your HIV doctor and/or HIV pharmacist knows exactly what drugs you are taking, and this includes medicines prescribed by another doctor, drugs bought from high street chemists, herbal remedies, and illicit or recreational drugs.

It is known that some drugs used to treat HIV can interact with some anti-hepatitis C drugs. For example, it is known that the anti-HIV drugs ddI (Videx) and d4T (stavudine, Zerit) interact with the hepatitis C drug, ribavirin.

Doctors have found that people who are receiving anti-hepatitis C treatment and are also taking abacavir (Ziagen) as part of their combination of anti-HIV drugs have a poorer response to anti-hepatitis C therapy. 

They found that people taking abacavir had lower levels of ribavirin in their blood to fight hepatitis C. They think that there is an interaction between abacavir and ribavirin and recommend that people taking the two drugs have their levels of ribavirin monitored so the dose can be adjusted if necessary.

Hepatitis B

Hepatitis B is a virus that affects the liver. Since it is transmitted in ways very similar to HIV – through sex and by contact with blood – many people with HIV are also infected with hepatitis C. Unlike HIV and hepatitis C, however, there is a highly effective vaccine against hepatitis B and everybody who is HIV-positive should receive this vaccine. The vaccine’s effectiveness should also be monitored at regular intervals to see if a booster dose is required.

Doctors use a number of tests to see if a person has been infected with hepatitis B. But in some people are said to have ‘occult’ (or hidden) hepatitis B because the tests don’t work properly.

Doctors in the Netherlands have found that approximately 5% of people with HIV and hepatitis B have occult hepatitis B. A low CD4 cell count and a high HIV viral load were risk factors for occult hepatitis B. More careful monitoring may therefore be needed in HIV/hepatitis B-coinfected people with weak immune systems.

HIV treatment in children

Since effective anti-HIV treatment became available, there has been a significant fall in the amount of illness and death caused by HIV seen in HIV-positive children.

But fewer drugs are available to treat HIV-positive children than are available for adults. Furthermore, the clinical trials that lead to the approval of the currently available anti-HIV drugs were conducted in adults, so a lot less is known about the effectiveness of treatment in children, the right doses of drugs to use, and the long-term benefits and risk of HIV treatment for children.

Now a small study has found that many children treated with efavirenz (Sustiva) have such low levels of the drug in their blood that there is a risk of resistance to the drug developing.

The children all weighed over 10kg and were aged between two years three months and 15 years. They received the appropriate weight-adjusted dose of efavirenz.

The researchers who conducted the study are calling for larger studies to be urgently undertaken to determine the safe dose of efavirenz in children.

HIV treatment during pregnancy

A mother can pass on HIV to her baby, but it is possible to reduce the risks of mother-to-child transmission of HIV to very low levels by the appropriate use of anti-HIV drugs during pregnancy, by having a caesarean delivery if the mother has a detectable viral load, and, in countries like the UK where there are safe alternatives, by not breastfeeding.

The anti-HIV drug nevirapine (Viramune) is often used during pregnancy. In the UK and similar countries, nevirapine should only be used as part of a combination of anti-HIV drugs. In countries where HIV treatment is difficult to obtain, pregnant women are sometimes given a single dose of nevirapine during labour. But this can lead to resistance to nevirapine developing and the drug should never be used in this way in the UK.

Nevirapine can also cause side-effects, the most notable being liver problems and rash. To reduce the risk of these occurring, the drug should not be given to women with a CD4 cell count of 250 or above.

A new study has shown that anti-HIV treatment that includes nevirapine achieves a rapid fall in viral load. The European study also found that women from West Africa experienced rapid falls in their viral load when treated during pregnancy.

The study compared rates of viral load decline between women taking nevirapine and nelfinavir, an alternative drug often used during pregnancy. The results of the study favoured nevirapine and the researchers “strongly suggest that an antiretroviral therapy-naïve woman with a CD4 cell count below 250 should begin nevirapine-based rather than nelfinavir-based antiretroviral therapy.” But given the recall of nelfinavir in the UK and Europe due to contamination, the findings of this study have rather been overtaken by events.

copy of copy of copy of New from NAM

Criminal HIV transmission

This new title from NAM provides evidence-based, up-to-date information in clear, layman’s language on aspects of HIV that may relate to the investigation, prosecution, and defence of criminal HIV exposure/transmission cases.

It’s primarily aimed at people who work within, or are in contact with, the criminal justice system. But the book is also likely to be useful for those who work at HIV support organisations, as well as HIV-positive individuals with an interest in criminal HIV transmission.

The book cost £14.95 for professionals, but is available at the discounted rate of £9.95 to voluntary organisations.

For more information or to order a copy of the book, please contact NAM by phoning 0207 8400050 or emailing info@nam.org.uk

Booklets

NAM's information booklets anti-hiv drugs, hiv & mental health, hiv & hepatitis and hiv & women have recently been updated.

Please order your free copies today.

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Please note we do charge professionals for these booklets, but don't forget, if your clinic is giving them out to patients you can order them for free. Overseas postage costs apply To find out more email info@nam.org or phone 020 7840 0050.