By Randall Osborne
West Coast Editor
Not so many years ago, skeptics branded the ideas that fueled biotechnology science fiction, and the industry still turns out, once in a while, an approach that sounds like something from a mad scientist's laboratory.
Peptide Morphing, for example.
Enanta Pharmaceuticals Inc. has bet its future on the technology, licensed from no less prestigious an entity than Harvard University. Enanta, of Cambridge, Mass., raised $20 million in a second round of private financing to advance the chemistry system.
The firm said its approach may transform peptides into small-molecule lead compounds by introducing spatial and chiral diversity, which makes them more stable, gives them permeable membranes and ensures effectiveness when given orally.
"We can look at a peptide and transform it into a small molecule that does not mimic the peptide, but brings into it characteristics that are much like natural products," said Peter Kliem, president of Cambridge, Mass.-based Enanta, which was founded in mid-1998. "This gives us an opportunity to influence pharmacological properties early on in the design."
More specifically, Peptide Morphing replaces one or more central bonds within a peptide (or other lead molecule) with stereochemically distinct derivatives, of which Enanta has a library. Such bond replacement, the company said, can improve any peptide-derived drugs or natural products.
Enanta starts with biologically active leads or targets, and then finds intervention points to boost potential compounds' effectiveness and improve safety profiles.
"Genomics is driving the identification of protein targets, and yet peptides don't make good drugs," Kliem told BioWorld Today. "If we swallow a spoonful of peptides, our stomach thinks it's a piece of steak."
Although the basic building blocks of life are amino acids, water, calcium and trace minerals, "the lesson in nature is that shape is fundamentally important," he added.
"The technology platform is broadly applicable, but our internal expertise is in the anti-infective domain," Kliem said. "In other areas, we're seeking collaborations. Pharmaceutical and biotech companies all have exciting peptides on the shelf," he added, although peptide experiments have not yielded much useful to date, with the exception of HIV proteases.
"It's a quest that has not paid off very well," he said.
Among the areas of collaboration the company might explore are opioid receptors and cancer, Kliem said.
"Ships weren't built to be in safe harbors, but we don't want to take a lot of risks," he said. "If someone has defined a target well, and some structural information is available, it certainly reduces the risk."
By working in the area of stereochemistry, and aiming at the shapes of peptide products to help boost their ultimate strength as drugs, Enanta is exploring a realm that seems obvious, Kliem acknowledged.
"In the end, once they're defined, many things that are important become obvious," he said.
Lead investor in the financing was Oxford Bioscience Partners. Others included Advent International, TVM Techno Venture Management, Caduceus Capital, Bank Vontobel, Alpinvest International B.V. and KB Lux Venture Capital.
TVM, a European concern, syndicated an equity financing of $5.1 million for Enanta one year ago.