Ritonavir Specifications

Product Name	Ritonavir
CAS Registry Number	155213-67-5
Molecular Formula	C37H48N6O5S2
Molecular Weight	720.946 g/mol
Purity	98%
Appearance	White powder
Package	1kg-25kg
Shelf life	2 years
Functions	Antiviral, therapy for HIV-1, potential inhibitor of COVID-19

Ritonavir Description

Ritonavir is an HIV protease inhibitor that interferes with the reproductive cycle of HIV. The mechanism of action of the anti-HIV drug lopinavir and ritonavir is to block the enzymes required for virus replication. It is often used in combination with other antiretrovirals and serves as both a protease inhibitor and a pharmacokinetic enhancer. Lopinavir/ritonavir have been shown to reduce coronavirus levels that cause SARS and MERS in animal studies.

Ritonavir is an HIV protease inhibitor that interferes with the reproductive cycle of HIV.

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Ritonavir Solubility / Properties

Ritonavir is poorly soluble in water, with solubility less than 1 mg/mL at physiological pH. This poor solubility can impact its bioavailability and absorption in the body, necessitating the use of formulations that enhance its solubility for effective therapeutic use.

Ritonavir Half-Life

The half-life of ritonavir is approximately 3 to 5 hours. However, due to its role as a CYP3A4 inhibitor, the half-lives of other drugs metabolized by this enzyme can be significantly prolonged when co-administered with ritonavir. This pharmacokinetic interaction is a key reason ritonavir is used as a booster for other protease inhibitors.

Ritonavir Applications

Ritonavir is indicated in combination with other antiretroviral agents for the treatment of HIV-1 infected patients (adults and children of 2 years of age and older).

Ritonavir is a potent inhibitor of cytochrome P450 3A4 (CYP3A4). This inhibition allows ritonavir to boost the levels of co-administered drugs that are substrates of CYP3A4, particularly other protease inhibitors used in the treatment of HIV.

Reference:

1. L. Morissette; S. Soukasene; D. Levinson; M. J. Cima; O. Almarsson (2003). "Elucidation of crystal form diversity of the HIV protease inhibitor ritonavir by high-throughput crystallization"
2. Hsieh, Yi-Ling; Ilevbare, Grace A.; Van Eerdenbrugh, Bernard; Box, Karl J.; Sanchez-Felix, Manuel Vincente; Taylor, Lynne S. (2012-05-12). "pH-Induced Precipitation Behavior of Weakly Basic Compounds: Determination of Extent and Duration of Supersaturation Using Potentiometric Titration and Correlation to Solid State Properties". Pharmaceutical Research. 29 (10): 2738–2753.
3. Nieminen, Tuija H.; Hagelberg, Nora M.; Saari, Teijo I.; Neuvonen, Mikko; Neuvonen, Pertti J.; Laine, Kari; Olkkola, Klaus T. (2010). "Oxycodone concentrations are greatly increased by the concomitant use of ritonavir or lopinavir/ritonavir". European Journal of Clinical Pharmacology. 66 (10): 977–985.