Question

Will subtype C progress more quickly than subtype B?

2 August 2007. Related: All topics, CD4 and viral load, Starting treatment.

I have been recently diagnosed with HIV subtype C.

Please can you tell me if this is a quicker progressor than sub type B? and if the medication that is used for HIV combination therapy works effectively on this subtype.

I understand that most of the funded research is for subtype B as this is most prevelant to the Western population.

Many thanks

Answer

Answer: Simon Collins

Although most research is in subtype B, several groups have reported very little difference between either rates of disease progression, or responses to treatment in people with sub-type B compared to other subtypes, including a UK study which compared 81 people with sub-type C to 408 people with subtype B.

Several studies including one from the UK and one from France, have also reported that there does not seem to be significant differences in response to treatment by subtype.

For you, it is probably more important to focus on your individual results in terms of CD4 and viral load counts, and then adherence when you come to start treatment.

Some research suggests that subtype C may be more vulnerable to some types of resistance (to NNRTIs when single dose nevirapine was used to prevent mother-to-child transmission; and to the K65R mutation associated with tenofovir resistance). In practice, this just means you need to be very good with adherence if you use these drugs in your combination in the future – though this is good advice for all drugs in all people.

In summary, there appear to be no major differences that affect your progression or response to treatment, but how you manage you health is very individual. When you come to use treatment, make sure you have all the information you need to get the best response, and be very careful to be adherent.