The role of plant expression platforms in biopharmaceutical development: possibilities for the future

ABSTRACT

Introduction: Plant-made vaccines have been in the pipeline for nearly thirty years. Generated stably in transgenic plants or transiently using virus expression systems, pharmaceuticals have been developed to address global pandemics as well as several emerging One Health Diseases.

Areas covered: This review describes the generation of plant-made vaccines to address some of the world’s most growing health concerns, including both infectious and non-communicable diseases, such as cancer. The review provides an overview of the research taking place in this field over the past three to five years. The PubMed database was searched under the topic of plant-made vaccine between the periods of 2014 and 2019.

Expert opinion: While vaccines and other biologics have been shown to be cheap safe and efficacious, they have not yet entered the marketplace largely due to regulatory constraints. The lack of an appropriate regulatory structure to guide plant-made vaccines through to commercial development has stalled efforts to provide life-saving medicines to low- and middle-income families. In my opinion, it is paramount that regulatory hurdles are mitigated to address emerging infectious diseases such as Ebola and Zika in a timely manner.

KEYWORDS:

• Transgenic plant
• virus expression vector
• HIV/AIDS
• influenza virus
• Ebola virus
• monoclonal antibody
• vaccine

Article highlights

• Plant-made vaccines are low in cost, efficacious, facile to upscale and highly adaptable for developing countries.

• Vaccines, monoclonal antibodies, and other pharmaceuticals can be produced stably in transgenic plants or transiently, via virus expression vectors.

• A microbicide to HIV/AIDS that has been produced in rice plants is more efficacious than its conventional counterpart.

• A variety of plant-derived treatments for Influenza virus, Ebola virus, and several One Health diseases have been developed for use as diagnostics and as vaccines.

• Plant virus nanoparticles can target solid tumors and can carry anticancer drugs as a payload to block cancer.

• The regulatory pathway for approval of plant-made vaccines and other biologics is unclear, creating a significant stumbling block for providing these innovative medicines to low- and middle-income countries.

Declaration of interest

The author has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.