Sustiva - let us get our facts straight...
There are 3 broad groups of AIDS drugs, based on the enzyme they target: Integrase Inhibitors (mentioned only for completeness, nobody has a serious contender in this group), Reverse Transcriptase (RT) Inhibitors and Protease Inhibitors (PI). HOWEVER, there are -3- classes of RT Inhibitors: the Nucleoside RT inhibitors (AZT and cousins 3TC, ddI, ddC, d4T), the NON-Nucleoside RT inhibitors, also referred to as NNRTIs (Nevirapine, delavirdine and now, Sustiva AKA Efavirenz or DMP-266) and the Nucleotide (Note: nucleo Tide as opposed to nucleo Side; one letter, BIG difference) RT inhibitors (Gilead's adefovir).
Sustiva has been tested in 2-drug combo with Crixivan, with pretty good results (see quotes below from AIDS Treatment News, #279, 9/19/97) - but that doesn't mean it can't work as well or better with Viracept. Remember, Crix will still have its side effects & difficult dosing schedule. I have read remarks (from The PWA Health Group's newsletter, out of Atlanta) that Sustiva slightly reduces Crixivan's effectiveness, but lengthens the time it stays in the blood, leading to speculation that high-dose Crixivan (3000-3600mg/day) may be necessary. Also, 2 drug combos have been pretty much ruled out as desirable treatment options. Has anyone seen a trial using Viracept and Crixivan, along with whatever else?
"Efavirenz (brand name SUSTIVA [tm], formerly known as DMP-266) in
combination with indinavir (Crixivan(tm)) resulted in an average viral
load reduction of 2.38 logs out of a possible 2.49 logs..."
"Efavirenz, being developed by DuPont Merck, in Wilmington, Delaware,
is a non-nucleoside reverse transcriptase inhibitor which is effective against many HIV variants which are resistant to other NNRTIs.
Resistance to efavirenz does develop slowly in laboratory tests,
however, so this drug should only be used in antiretroviral
combinations, never alone."
AIDS Treatment News, #279, 9/19/97 |
