Primrose Bio’s CRM197 - The Unsung Hero Powering Next-Gen Vaccines

Primrose Bio’s CRM197 – The Unsung Hero Powering Next-Gen Vaccines

In the world of vaccine innovation, few ingredients are as quietly essential as CRM197—a carrier protein that’s become the backbone of modern conjugate vaccines. At the forefront of this field is Primrose Bio, whose PeliCRM197® is the only commercially available CRM197 used marketed vaccines.

What Is CRM197?

CRM197 is a genetically detoxified mutant of diphtheria toxin, engineered to be non-toxic while retaining its ability to stimulate strong immune responses. This makes it an ideal carrier protein for conjugate vaccines, which link polysaccharides (complex sugars from bacteria) to proteins to boost immunogenicity, especially in infants and the elderly.

Primrose Bio’s PeliCRM197®:

Industry-Leading Technology

Primrose Bio produces PeliCRM197® using its proprietary Pfenex Expression Technology®, a robust protein expression platform powered by Pseudomonas fluorescens. This technology delivers high yields, unmatched purity, and scalability—capable of producing CRM197 from milligrams for research to kilograms for commercial vaccine manufacturing. The Pfenex platform has an extensive regulatory and safety record, with six marketed products utilizing it.

Regulatory Strength

PeliCRM197® is supported by a Drug Master File (DMF) filed with the US FDA, simplifying regulatory submissions for vaccine developers globally. This regulatory support, paired with GMP certification since 2011, positions Primrose Bio as a trusted supplier in the vaccine ecosystem.

Real-World Impact

Primrose Bio’s CRM197 is found in several high-profile vaccines, including Merck’s VAXNEUVANCE® and CAPVAXIVE®, as well as Pneumosil® and MenFive® from the Serum Institute of India. The recent FDA approval of CAPVAXIVE underscores the protein’s critical role in advancing adult pneumococcal vaccines.

Strategic Partnerships

Primrose Bio recently partnered with Intravacc, a leading contract development and manufacturing organization, to streamline the development and supply of conjugate vaccines. This collaboration combines Intravacc’s expertise in vaccine process development with Primrose Bio’s ultra-pure, scalable CRM197 supply, offering a seamless solution for both research and commercial vaccine developers.

Why It Matters

Consistency & Quality: PeliCRM197® is the highest-purity CRM197 commercially available, with >95% purity and low endotoxin levels.
Scalability: From lab research to global vaccine rollout, Primrose Bio guarantees a reliable supply chain.
Regulatory Compliance: With a US FDA DMF and global regulatory support, vaccine developers can accelerate their path to market.
Industry Adoption: Used by leading pharmaceutical companies including Merck and Serum Institute of India.

The Future of Vaccine Manufacturing

Primrose Bio’s integrated technology platform, combining advanced protein engineering with scalable manufacturing, is enabling the next generation of vaccines and therapeutics. As the demand for safe, effective vaccines grows, the importance of reliable, high-quality carrier proteins like CRM197 will only increase.

Conclusion

While the world’s attention often focuses on the final vaccine product, it’s the innovation behind the scenes—like Primrose Bio’s CRM197—that makes these breakthroughs possible. With its proven track record, regulatory strength, and strategic partnerships, Primrose Bio is quietly revolutionizing the landscape of vaccine development.