Print this article The difficulty of learning the technology behind mRNA vaccines poses a major obstacle to President Joe Biden's proposal aiding poor countries by defying the pharmaceutical industry and waiving patent protections for COVID-19 vaccines. The rationale for the patent waiver would be to allow developing countries to reproduce currently existing COVID-19 vaccines without having to worry about getting sued by the pharmaceutical companies that hold the patents. But in the case of the mRNA vaccines produced by Pfizer/BioNTech and Moderna, doing so would be very difficult. As of March, mRNA vaccines accounted for 43% of the COVID-19 vaccines produced, according to British software company Airfinity.