Merck's new anti-CMV infection drug letermovir announces production in China

On November 18, the CDE official website showed that the marketing application of Merck’s cytomegalovirus infection drugs Letermovir tablets and Letermovir injection were accepted by CDE.

Cytomegalovirus (CMV) is a herpes virus group DNA virus. CMV infection is very common in the population, usually clinically mild or asymptomatic. But for immunodeficiency patients, CMV infection is a serious and life-threatening disease, especially in allogeneic hematopoietic cell transplant recipients, the incidence of CMV disease is as high as 50% to 60%, and it may progress to CMV disease.

The standard treatment for CMV infection is intravenous Ganciclovir or oral valganciclovir, or intravenous foscarnet or Cidofovir. Although effective, these treatments have significant clinical drug-specific effects, including bone marrow transplantation and nephrotoxicity, making the use of these drugs in allogeneic hematopoietic cell transplant recipients more difficult.

According to the Insight database, currently approved drugs for the treatment of CMV infection in China are ganciclovir, acyclovir, valganciclovir, and Vidarabine, while foscarnet sodium and foscarnet sodium chloride injection are available in China. Approved indications include cytomegalovirus retinitis in patients with AIDS (AIDS). Cidofovir has not yet been approved in China. These drugs have been approved earlier in China. In the past ten years, no new drugs for the treatment of CMV infection have been approved in China. At present, recipients of allogeneic hematopoietic cell transplantation in China urgently need safe and effective anti-CMV preventive measures.

Lettermovir is a potent inhibitor of CMV DNA telomerase, which targets the viral terminal enzyme subunit pUL56 (this subunit is one of the components of the terminal enzyme involved in viral DNA cleavage and packaging). Does not act on any enzymes in the human body. Clinical studies have shown that letermovir has good safety and efficacy. After 28 days of treatment, no cytomegalovirus was detected in the patient's body, and there is no cross-resistance compared with other approved drugs.

The drug was originally developed by AiCuris and licensed to Merck in 2011. In the United States, the European Union and Japan, the drug has been granted orphan drug designation for the prevention of CMV infection in high-risk groups. In addition, in the United States, the drug has also been granted fast-track status. In November 2017, Letermovir tablets and injections were approved by the FDA for marketing under the trade name Prevymis, becoming the first drug approved for the treatment of cytomegalovirus in the United States in the past 15 years. In January 2018, Letermovir tablets were approved again in the European Union.

The approval of Prevymis is based on positive data from a pivotal Phase III clinical study. The data showed that after 24 weeks of treatment with Prevymis, CMV occurred in 38% of patients, compared with 61% in the placebo group. And at the 24th week after transplantation, the all-cause mortality rate in the Prevymis treatment group was lower than that in the placebo group (12% vs 17%).

Currently, Merck has not announced the specific sales of Prevymis. It is reported that the drug was initially priced at US$270/day for injections and US$195/day for tablets. 100 days is a course of treatment. Merck expects that the drug’s sales in 2020 may reach US$370 million, accounting for approximately the company’s annual pharmaceutical business revenue. 1%. Due to price reasons, the drug was rejected by NICE in the UK in June 2018. In March 2019, after Merck offered a certain discount, the drug was recommended by NICE to prevent the reactivation of cytomegalovirus in patients undergoing blood stem cell transplantation.

In China, letermovir tablets and injections were approved for clinical use in China in June this year for cytomegalovirus (CMV) seropositive adult recipients of allogeneic hematopoietic stem cell transplantation (HSCT) [R+] prevention of CMV Reactivation and disease. After a lapse of about 5 months, Latermovir was reported for production in China. It is expected that this anti-CMV infection drug can be approved in China as soon as possible.