Candidate: Vaccine to treat COVID-19

Category: VAX

Type: Measles vector vaccine engineered to express SARS-CoV-2 proteins on its surface. The measles virus vector platform based on a vector originally developed at the Institut Pasteur.

2021 Status: MERCK HALTS DEVELOPMENT OF V591–Merck & Co. said January 25 it will halt development of V591 and another COVI-19 vaccine candidate, V590, while continuing development of two drug candidates against the virus, molnupiravir (MK-4482) and MK-7110. Merck said V591 and V590 generated weaker immune responses than other unnamed COVID-19 vaccines.

Merck and partners plan to submit the results of Phase I studies for V591 and V590 for future publication in a peer-reviewed journal. The company also said it will continue to study the potential of the platforms behind V591 and V590, as well as “pursue broader pandemic-response capabilities.”

2020 Status: Merck & Co. disclosed September 9 on that it had begun recruiting patients for a Phase I/II trial (NCT04498247) designed to identify the V591 dose that achieves the target immune response in humans based on preclinical or early clinical data. The randomized, double-blind, placebo-controlled study will evaluate the safety, tolerability, and immunogenicity of the vaccine candidate in up to 260 healthy participants in Belgium. The trial’s estimated primary completion date is April 26, 2022.

Merck CEO Kenneth C. Frazier in July told Tsedal Neeley, Naylor Fitzhugh Professor of Business Administration at Harvard Business School: “I think when people tell the public that there’s going to be a vaccine by the end of 2020, for example, I think they do a grave disservice to the public.”

“I think at the end of the day, we don’t want to rush the vaccine before we’ve done rigorous science,” Frazier cautioned in an interview published July 13 in the School’s online publication Working Knowledge. “We’ve seen in the past, for example, with the swine flu, that that vaccine did more harm than good. We don’t have a great history of introducing vaccines quickly in the middle of a pandemic. We want to keep that in mind.”

In May, Merck agreed to acquire Themis for an undisclosed price, in a deal that closed in June, transforming Themis into a wholly-owned subsidiary of the buyer. Themis has developed a pipeline of vaccine candidates and immune-modulatory therapies using a platform based on a measles virus vector it licenses from the Institut Pasteur. The pipeline includes a COVID-19 vaccine candidate that is in preclinical development, with clinical studies planned to start later in 2020.

The Institut Pasteur had headed a COVID-19 vaccine consortium that included Themis and the University of Pittsburgh’s Center for Vaccine Research (CVR). The consortium has been awarded an initial $4.9 million by CEPI, the Coalition for Epidemic Preparedness Innovations. As a first step, CEPI funding will support the preclinical testing, initial manufacture of vaccine materials, and preparatory work for Phase I studies, CEPI said in March.

In connection with the acquisition, Merck, Institut Pasteur, and CEPI agreed to address the COVID-19 pandemic by developing, manufacturing, and distributing the vaccine on a global basis, with “pricing that makes the vaccine both available around the world and accessible to those who need it, including low-income, middle-income and high-income countries based on the medical need when the vaccine may become available.”

COVID-19: 300 Candidates and Counting

To navigate through the >300 potential therapeutic and vaccine options for COVID-19, GEN has grouped the candidates into four broad categories based on their developmental and (where applicable) clinical progress:

FRONT RUNNER – the most promising therapeutics/vaccines based on clinical progress, favorable data or both.

DEFINITELY MAYBE – earlier phases with promising partners, or more advanced candidates in development that have generated uneven data

KEEPING AN EYE ON… – interesting technology, attracting notable partners, or both, but preliminary data.

TOO SOON TO TELL – longshots pending additional experimental and/or clinical data.

GEN has also tagged the most common treatment types:


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