Letermovir: Treatment of human cytomegalovirus infection, antiinfective agent

Novel therapies are urgently needed for the management of cytomegalovirus (CMV) infection in high-risk patients. Currently licensed agents target the viral DNA polymerase, and although they are effective, they are fraught with toxicities to patients. Moreover, the emergence of antiviral resistance is an increasing problem, particularly for patients on long-term suppressive therapy. A new agent, letermovir (AIC-246), shows great promise for the management of CMV infection. Advantages include good oral bioavailability, lack of toxicity and the apparent absence of drug-drug interactions. Letermovir has a novel mechanism of action, exerting its antiviral effect by interfering with the viral pUL56 gene product and in the process disrupting the viral terminase complex. This agent demonstrates substantial promise as an alternative to more toxic antivirals in patients at high risk for CMV disease, particularly in the transplant setting.