Analytical Techniques in the Analysis of Darunavir and Ritonavir: A Review

Quality by design tool-evaluated stability-indicating ultra-performance liquid chromatography method for the determination of drugs (ritonavir and darunavir) used to treat the human immunodeficiency virus/acquired immunodeficiency syndrome

Ritonavir and darunavir were examined using a ultra-performance liquid chromatography (UPLC) approach in pharmaceutical dosage forms. The small number of analytical studies that are currently available do not demonstrate the method's stability or nature. The study sought to assess both chemicals using a stability-indicating approach with a relatively short run time. The HSS C18 (100 × 2.1 mm), 2-mm column was used for the chromatographic separation, and isocratic elution was used to achieve this. In the mobile phase, methanol and 0.01 M phosphate buffer (pH 4.0) were included in a 60:40 (v/v) ratio. Throughout the analysis, the flow rate was kept at 0.2 mL min-1 , and a photodiode array detector set to 266 nm was used to find the major components. The proposed method showed a linear response (r2  > 0.999), and the accuracy was between 98.0% and 102.0%. The precision data showed relative standard deviation ≤1.0%. The UPLC method for quantification of ritonavir and darunavir in pharmaceutical dosage forms using a very short run time of under a minute is the subject of the proposed article. To meet current regulatory criteria, the quality by design idea was used in the method performance verification.

Analytical Methods for the Determination of Major Drugs Used for the Treatment of COVID-19. A Review

At the beginning of the COVID-19 outbreak (end 2019 - 2020), therapeutic treatments based on approved drugs have been the fastest approaches to combat the new coronavirus pandemic. Nowadays several vaccines are available. However, the worldwide vaccination program is going to take a long time and its success will depend on the vaccine public's acceptance. Therefore, outside of vaccination, the repurposing of existing antiviral, anti-inflammatory and other types of drugs, have been considered an alternative medical strategy for the COVI-19 infection. Due to the broad clinical potential of the drugs, but also to their possible side effects, analytical methods are needed to monitor the drug concentrations in biological fluids and pharmaceutical products. This review deals with analytical methods developed in the period 2015 - July 2021 to detect potential drugs that, according to a literature survey, have been taken into consideration for the treatment of COVID-19. The drugs considered here have been selected on the basis of the number of articles published in the period January 2020-July 2021, using the combination of the keywords: COVID-19 and drugs or SARS-CoV-2 and drugs. A section is also devoted to monoclonal antibodies. Over the period considered, the analytical methods have been employed in a variety of real samples, such as body fluids (plasma, blood and urine), pharmaceutical products, environmental matrices and food.

Darunavir: A comprehensive profile

Darunavir: (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-yl [(2S,3R)-4-{[(4-aminophenyl)sulfonyl] (isobutyl)amino}-3-hydroxy-1-phenyl-2-butanyl]carbamate is a synthetic non-peptide protease inhibitor. On June 2006, it was first approved by the Food and Drug administration (FDA) for treatment of resistant type-1 of the human immunodeficiency virus (HIV). In July 2016, the FDA expanded the approval for use of darunavir in pregnant women with HIV infection. Darunavir prevents the replication of HIV virus by inhibiting the catalytic activity of the HIV-1 protease enzyme, and selectively inhibits the cleavage of HIV encoded Gag-Pol polyproteins in virus-infected cells, which prevents the formation of mature infectious virus particles. Darunavir is unique among currently available protease inhibitors because it maintains antiretroviral activity against a variety of multidrug-resistant HIV strains. This article discusses, by a critical extensive review of the literature, the description of darunavir in terms of its names, formulae, elemental composition, appearance, and use in the treatment of HIV-infected patients. The article also discusses the methods for preparation of darunavir, its physical-chemical properties, analytical methods for its determination, pharmacological properties, and dosing information.