Progress of Middle East respiratory syndrome coronavirus vaccines: a patent review

Abstract

Middle East respiratory syndrome coronavirus (MERS-CoV) has emerged as a new pathogen, causing severe complications and a high case fatality rate. No direct treatments are available as yet, highlighting the importance of prevention through suitable vaccination regimes. The viral spike (S) protein has been characterized as a key target antigen for vaccines. In particular, S protein domains have been utilized to produce high titers of neutralizing antibodies. Areas covered: Since the first report of MERS-CoV infection, a limited number of MERS-CoV-specific patents have been filed. Patents related to MERS-CoV are categorized into three areas: treatments, antibodies, and vaccines (receptor-related). This review mainly focuses on the types and efficacies of vaccines, briefly covering treatments and antibodies against the virus. MERS-CoV vaccine forms and delivery systems, together with comparable development strategies against SARS-CoV are additionally addressed. Expert opinion: Vaccines must be combined with delivery systems, administration routes, and adjuvants to maximize T-cell responses as well as neutralizing antibody production. High immune responses require further study in animal models, such as human receptor-expressing mice, non-human primates, and camels. Such a consideration of integrated actions should contribute to the rapid development of vaccines against MERS-CoV and related coronaviruses.

Keywords: Animal model; MERS-CoV; neutralizing activity; receptor DPP4; spike protein; vaccine administration route; vaccine type.