In any case, it's important health care providers and people living with HIV are aware of the superiority of the three times daily dosing of indinavir, as many doctors and patients have already made the switch to twice daily dosing. Indinavir, in combination with another protease inhibitor, is still being studied for twice daily dosing in other studies. Ritonavir is able to substantially increase indinavir levels in blood as well as slow the rate at which indinavir is passed out of the body. Preliminary, short-term studies appear to show that this regimen allows indinavir to work well with twice daily dosing, while the combination also seems to eliminate the need to avoid taking food with indinavir. However, it's important to recognize this is based on very early data.
Studies are ongoing to determine the optimal doses of indinavir and ritonavir when used together.
Longer-term data will help confirm whether the drug is useful when used in these combinations in twice daily dosing regimens. The lesson learned here is something that Project Inform has been cautioning about for some time with regard to simpler and easier regimens using current available therapies. While people want, need and deserve simpler regimens, simply changing a regimen from three times to twice daily dosing is not the solution. The lesson here is that it takes larger, long-term studies to accurately determine how well a drug works in different dosing regimens. It can be potentially dangerous to make treatment decisions based on small exploratory studies.