ledipasvir

ledipasvir
IUPAC name	Methyl {(2S)-1-[(6S)-6-{2-[(2S,5S)-1-{(2S)-2-[(methoxycarbonyl)amino]-3-methylbutanoyl}-5-methylpyrrolidin-2-yl]-1H-imidazol-5-yl}-5-{4-{2-[(2S,5S)-1-{(2S)-2-[(methoxycarbonyl)amino]-3-methylbutanoyl}-5-methylpyrrolidin-2-yl]-1H-imidazol-5-yl}phenyl}pyridin-2-yl]pyrrolidin-2-yl}carbonyl]carbamate
Width	200
CAS number	1256388-51-8
PubChem	67505836
DrugBank	DB09133
UNII	013E6EYN5I
ATC prefix	J05
ATC suffix	AP54

ledipasvir is a direct-acting antiviral medication used in combination with other agents for the treatment of chronic hepatitis C virus infection. It is a potent inhibitor of the NS5A protein, a key component of the HCV replication complex, and is a critical component of several highly effective therapeutic regimens. Developed by Gilead Sciences, it is most commonly administered as a fixed-dose combination tablet with sofosbuvir, marketed under the brand name Harvoni.

Medical uses

Ledipasvir is indicated, in combination with sofosbuvir, for the treatment of chronic HCV genotype 1 infection in adults, as recommended by guidelines from the American Association for the Study of Liver Diseases and the Infectious Diseases Society of America. This regimen is also approved for use in patients co-infected with human immunodeficiency virus and for those with advanced liver cirrhosis, including individuals who have undergone a liver transplantation. Clinical trials, such as the ION-1 and ION-3 studies, demonstrated sustained virologic response rates exceeding 95% in treatment-naïve patients without cirrhosis, revolutionizing the standard of care. The combination therapy is administered orally once daily, typically for 8 to 12 weeks, depending on patient history and the presence of compensated cirrhosis.

Pharmacology

Ledipasvir exerts its antiviral effect by targeting the NS5A protein, which is essential for HCV RNA replication and virion assembly. It binds to the N-terminal domain of NS5A, disrupting its normal function in the viral life cycle. The drug achieves high intracellular concentrations in the liver, its primary site of action, and is a substrate for the P-glycoprotein efflux transporter. Pharmacokinetic studies show it has a long half-life, supporting once-daily dosing, and its absorption can be increased when taken with food. The metabolism of ledipasvir is minimal, with the majority of the drug excreted unchanged in the feces.

Adverse effects

The fixed-dose combination of ledipasvir and sofosbuvir is generally well-tolerated. The most commonly reported adverse events in clinical trials were fatigue, headache, and nausea. Serious side effects are rare but can include symptomatic bradycardia when co-administered with amiodarone, a risk that prompted a FDA warning. There is also a potential for drug interactions with potent inducers of P-glycoprotein, such as rifampin, or with agents that increase gastric pH, like omeprazole, which may reduce ledipasvir concentrations.

Chemistry

Ledipasvir is a complex organic molecule belonging to the chemical class of benzimidazole derivatives. Its molecular formula is C₄₉H₅₄F₂N₈O₆ and it has a molecular weight of 889.0 g/mol. The compound exists as a single stereoisomer due to multiple chiral centers, and its synthesis involves sophisticated asymmetric synthesis techniques. The solid form of the drug substance is typically a crystalline solid that is practically insoluble in water.

History

The discovery and development of ledipasvir were spearheaded by researchers at Gilead Sciences in Foster City, California, as part of a broader program to develop all-oral regimens for hepatitis C. Following promising preclinical data, it entered clinical development and was studied in combination with the nucleotide analog inhibitor sofosbuvir. The U.S. Food and Drug Administration granted approval for the ledipasvir/sofosbuvir combination in October 2014, based on data from the pivotal ION clinical trial program. Subsequent approvals were granted by the European Medicines Agency and other regulatory bodies worldwide.

Society and culture

The introduction of the ledipasvir/sofosbuvir combination, Harvoni, had a profound societal impact due to its high cost, sparking significant debate over drug pricing and access to healthcare in systems like the National Health Service in the United Kingdom and among insurers in the United States. Its effectiveness led to a dramatic shift in the treatment paradigm for hepatitis C, moving away from interferon-based therapies. The drug has been the subject of patent disputes, including litigation involving Merck & Co., and its development is considered a landmark achievement in the field of antiviral drug discovery.

Category:Antiviral drugs Category:Hepatitis C