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The Peptide Drug That Needed a Factory: Enfuvirtide, T-20 and the Limits of Peptide Manufacturing
In the 1990s, a team of scientists realized that a piece of the HIV envelope protein, when made as a small peptide, could block the virus from entering cells. Turning that idea into a drug meant making a 36-amino-acid peptide at a scale no one had attempted for a synthetic peptide.
Key takeaways
- Enfuvirtide, also called T-20, is a 36-amino-acid peptide derived from the HIV protein gp41.
- Work at Duke University by Dani Bolognesi and Thomas Matthews, with Trimeris, led to its development.
- It blocks the fusion of the virus with the host cell.
- Manufacturing it required more than a hundred steps and a combination of solid-phase and solution-phase chemistry.
- It was approved in 2003 and showed what large-scale peptide manufacturing could look like.
A piece that blocks the whole
HIV enters cells by folding its envelope protein into a hairpin-like structure, bringing the virus and cell membranes together. The folding relies on two helical regions interacting. A peptide matching one of those regions can lock onto the other and jam the process. Matthews and Bolognesi’s group at Duke found that a peptide from the second helical region was a potent blocker of viral entry.
From laboratory peptide to product
Making a few milligrams of a 36-amino-acid peptide for research is routine. Making kilograms was another matter. At that time most peptide drugs were much shorter. Enfuvirtide had to be dosed in relatively large amounts, so the supply requirement was huge.
Roche and Trimeris developed a hybrid approach. Several shorter fragments were made by solid-phase synthesis, purified, and then joined in solution. The total process involved over a hundred separate chemical steps. It was one of the most complex peptide manufacturing efforts of its time and required dedicated facilities.
Why length is hard
As we describe in our length and yield post, each added amino acid is another chance for a small error. In a 36-residue chain, a coupling efficiency of 99 percent leaves only about 70 percent of the chains perfect. The more demanding the purity target, the more chromatography is needed to remove deletion and truncation products, as in our post on those impurities.
Approval and legacy
The US FDA approved enfuvirtide in 2003 as the first drug of its class, an HIV fusion inhibitor. It was given by injection twice a day and was used mainly for patients whose virus had become resistant to other drugs. Newer oral drugs have since displaced it, but its manufacturing program set a model for large peptides, and many of the lessons are still used.
What it shows researchers
- Peptides can be designed from a piece of a larger protein.
- Longer peptides need more careful analysis, as in HPLC versus mass spectrometry.
- Lot-to-lot consistency depends on process control, which is why batch-to-batch variability matters.
- Documentation should match the product in hand, as in our lab report checklist.
The bottom line
Enfuvirtide showed that peptide drugs could be made at industrial scale, and that doing so is a serious engineering challenge. For a closer look at how we document the research compounds we list, visit our lab report page and catalog.
Related reading
- Solid-phase peptide synthesis
- Batch-to-batch variability
- Why purity alone is not enough
- Browse the full Research Library
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- Read the lab reports (COA)
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For laboratory research use only. Not for human or veterinary use, and not intended to diagnose, treat, cure or prevent any condition. This article is educational and is not medical advice.