One person’s weed is another’s flower. A good example of this is spiral-tufted bryozoan, an invasive marine organism that fouls up marine environments. Although considered a pest by many, spiral-tufted bryozoan is much sought after by researchers since it can produce biostatin 1 — a chemical critical to the development of promising new drugs to treat HIV/AIDS, Alzheimer’s disease and cancer.
Although this bryozoan is abundant, bryostatin 1 is very scarce because it’s difficult to harvest from the sea creature and complex to synthesize. In fact, the National Cancer Institute’s stock of bryostatin 1 is nearly depleted from supplying over 40 clinical trials. So Stanford chemists have developed a new, easier way to synthesize bryostatin 1, as recently reported in Science.
Paul Wender, PhD, a professor of chemistry and of chemical and systems biology at Stanford, has been working for years to develop bryostatin analogs that are more effective for drug development. However, the dwindling supply of bryostatin 1 inspired him to synthesize the drug itself.
“Ordinarily, we’re in the business of making chemicals that are better than the natural products,” Wender said in a recent Stanford news release. “But when we started to realize that clinical trials a lot of people were thinking about were not being done because they didn’t have enough material, we decided, ‘That’s it, we’re going to roll up our sleeves and make bryostatin because it is now in demand.’”
The researchers devised a much simpler synthesize process, cutting the steps down from 57 to 29. They also dramatically increased the yield, making it tens of thousands of times more efficient than extracting bryostatin from spiral-tufted bryozoan and significantly more efficient than the previous synthetic approaches. And they confirmed with a wide range of tests that their synthetic bryostatin was identical to a natural sample supplied by NCI.
So far, the team has produced over two grams of bryostatin 1, and a single gram can treat about 1000 cancer patients or 2000 Alzheimer’s patients, according to their paper. After scaling up production, they expect manufacturers to produce about 20 grams per year to meet clinical and research needs, Wender said in the news release.
They also expect their work could facilitate research using bryostatin analogs derived from their synthesis process. The paper explains that these analogs “are proving to be more effective and better tolerated in comparative studies with cells, disease models in animals, and ex vivo samples taken from HIV-positive patients.”
This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.