Kaletra not associated with raised blood pressure, manufacturer review reports

People taking a HAART combination including the protease inhibitor Kaletra (lopinavir/ritonavir) are no more likely to develop high blood pressure than those taking another protease inhibitor nelfinavir (Viracept) or the NNRTI efavirenz (Sustiva).

The research, sponsored by Kaletra’s manufacturer Abbott, was presented at the recent Eighth International Workshop on Adverse Drug Reactions and Lipodystrophy in HIV in San Francisco and contradicts another study published earlier this year (Crane 2006).

That observational study suggested people taking Kaletra were at threefold higher risk of developing high blood pressure when compared to people taking other regimens, but this increased risk was largely due to increases in body mass after starting a HAART combination containing the drug.

It is well known that HIV drugs can cause metabolic side-effects, in particular increases in lipid levels, leading to concern that these elevations could increase the long-term risk of cardiovascular disease.

Raised blood pressure (hypertension) is also a recognised risk factor for cardiovascular disease, but little is known about the impact of HAART on blood pressure and the studies that have been published have produced conflicting data

The new study is a retrospective analysis of data from two trials. The first was carried out in 863 HIV-infected people taking HAART for the first time, randomised to receive Kaletra plus stavudine and lamivudine or nelfinavir plus stavudine and lamivudine.

The second was in 155 treatment-naïve people randomised to receive either Kaletra plus zidovudine and lamivudine or nelfinavir plus zidovudine and lamivudine.

In the first study there were no clinically significant differences between Kaletra and nelfinavir-treated individuals in terms of systolic or diastolic blood pressure or adverse events of hypertension. There was a statistically significant rise in systolic blood pressure in both groups but it was not thought to be of any clinical importance.

There were no clinically significant shifts in blood pressure from baseline observed after 48 weeks of follow-up.

In the second study there were no significant changes in systolic blood pressure after 48 weeks with either Kaletra or efavirenz, although there was a small but significant rise in diastolic blood pressure in the efavirenz group but not with Kaletra.

The researchers say the findings appear to contradict the earlier study and show that treating HAART-naïve people with a combination containing Kaletra does not adversely affect their blood pressure compared to nelfinavir or efavirenz-containing combinations.

Due to the fact that patients in the second study, all of whom took zidovudine, had a significant increase in systolic blood pressure, they add that choice of the nucleoside backbone is important could affect blood pressure too.

Patients in the first study- none of whom took zidovudine- did not have raised systolic BP. But they concede that comparing results from two different studies should be done cautiously.