Invirase and Fortovase: new dosing regimens approved by FDA
The FDA approved, on 24 December 2003, new dosing regimens for the two available formulations of saquinavir, Invirase (hard gel capsule) and Fortovase (soft gel capsule). The newly approved dosing regimen for both Invirase and Fortovase is 1000 mg BID (twice a day) co-administered with ritonavir 100 mg BID.
For Invirase, the new ritonavir boosted regimen replaces the previously approved regimen. As stated in the revised label, Invirase should never be used without ritonavir.
For Fortovase, the ritonavir boosted regimen allows a reduced pill burden and ease of administration compared to the previously approved regimen. Unboosted Fortovase, however remains a dosage option for patients who are unable to tolerate ritonavir.
The approval of the new dosing regimens was based on pharmacokinetic and safety data. Both boosted regimens of saquinavir provide plasma concentrations exceeding that of unboosted Fortovase.
Important changes in the Invirase and Fortovase labels include drug interaction information relevant to the co-administration of ritonavir.
The revised labelling will be available in the coming weeks through the index at:
Source: FDA press release
Until now Invirase and Fortovase were one of the most expensive and least effective PIs when used according to the label. Now with an approved boosted setting at least in Europe the daily price will now decrease.