Abacavir with dolutegravir and lamivudine

How it works

Dolutegravir blocks integration of viral DNA into the host genome by inhibiting HIV integrase, while abacavir and lamivudine are incorporated into nascent viral DNA to terminate chain elongation and inhibit reverse transcriptase.

Prescribing in practice

• Screen for the HLA-B*57:01 allele before starting and never prescribe if positive, as carriers are at high risk of potentially fatal abacavir hypersensitivity; this combination is unsuitable for anyone with prior abacavir hypersensitivity.
• Because the dose is fixed, this product is not appropriate where dose adjustment of any component is needed, such as significant renal impairment affecting lamivudine, and an alternative regimen should be used.
• Separate administration from polyvalent cation antacids and supplements, and review concomitant metformin and certain anticonvulsants, as dolutegravir absorption and interactions can be clinically significant.

Monitoring

Monitor viral load and CD4 count to confirm virological response, alongside renal and hepatic function and any features suggesting hypersensitivity.

Counselling the patient

• Carry the alert card and stop the tablet immediately, contacting your clinic, if you develop fever, rash or other hypersensitivity symptoms.
• Take it at the same time each day and do not restart abacavir-containing products if you have ever reacted to them.
• Tell the team about all other medicines, including antacids and supplements taken over the counter.

Evidence & guidelines

UK and international HIV guidelines support integrase-inhibitor-based single-tablet regimens such as this for first-line treatment, with the MHRA emphasising mandatory HLA-B*57:01 screening before any abacavir-containing product.