Drug Discovery in Seattle 2015: An Updated History

FDA approval in 2014 and is used to treat chronic lymphocytic leukemia, relapsed follicular B-cell non-Hodgkin lymphoma, and small lymphocytic lymphoma.

Seattle Genetics has focused most of its R&D efforts developing antibody drug conjugates, a type of cancer drug that links a guiding antibody to a tumor-killing toxin. Its first such drug, brentuximab vedotin (Adcetris), was approved by the FDA in 2011 for patients who have relapsed with Hodgkin lymphoma or who have systemic anaplastic large cell lymphoma. It targets a protein on the surface of the cancer cells known as CD30.

New Uses Approved for Four Already Discovered Drugs

PathoGenesis (along with Children’s Hospital in Seattle) developed inhalable tobramycin (Tobi) to treat Pseudomonas aeruginosa infections in patients with cystic fibrosis. The FDA approved the drug in late 1997. Developing this medicine as an inhalation therapy for CF was a novel use for tobramycin, which was discovered in 1975. Chiron acquired PathoGenesis in 2000, and Novartis in turn bought Chiron in 2006.

Corus Pharma developed an inhaled form of the antibiotic aztreonam lysine for bacterial infections in the lungs of CF patients. The discovery of aztreonam dates back to 1982. Gilead purchased Corus in 2006 and went on to win FDA approval in February 2010 for the inhaled form of the antibiotic, which is sold under the brand name Cayston.

Immunex began selling mitoxantrone (Novantrone) after American Cyanamid (later acquired by Wyeth, which was then bought by Pfizer) acquired a majority stake in the company in 1993. The drug, a type II topoisomerase inhibitor, had been used since 1987 to treat acute nonlymphocytic leukemia, acute myeloid leukemia, and metastatic breast cancer. In 1997, Immunex was cleared to use it as a treatment for pain in late-stage prostate cancer patients. Immunex rode the expanded-use wave again in 2000, when the FDA approved mitoxantrone to reduce neurological disability and/or the frequency of clinical relapses in multiple sclerosis patients. In late 2002, Amgen sold the U.S. rights to mitoxantrone for several diseases to Serono, who then turned around four months later and peddled the rights to OSI Pharmaceuticals.

Omeros’s Omidria won FDA approval in May 2014 for use during cataract and lens replacement surgery, but the drug wasn’t launched until early April 2015, so it’s not clear yet how well it will sell. The drug is a proprietary combination of two well-known medicines, phenylephrine (an alpha1-adrenergic receptor agonist) and ketorolac,(an anti-inflammatory drug that blocks the cyclooxygenase enzyme). It is used to maintain pupil size and reduce postoperative ocular pain by preventing pupil constriction. Ketorolac was originally developed by Syntex in 1989, while phenylephrine has been available for decades in the U.S. and is most frequently used as a decongestant. The scientists at Omeros came up with the idea of combining these two drugs into one solution to prevent problems that can crop up during eye surgery.

Three Drugs Acquired and Developed by Seattle Based Biotechs

Corixa acquired cancer drug tositumomab (Bexxar) by purchasing its developer, Coulter Pharmaceuticals, for $900 million in 2000. Coulter had an agreement with SmithKline Beecham (now GlaxoSmithKline) to share marketing and profits for the drug. The FDA approved tositumomab in late 2003 to treat follicular non-Hodgkin’s lymphoma. Difficulties with the “commercial acceptance” of this hard-to-prepare and administer radioactive drug led Corixa to transfer the drug’s marketing and development rights to Glaxo in 2004. The British firm then bought Corixa two years later, primarily for its vaccine adjuvants (see below).

Panitumumab (Vectibix) is a cancer drug meant to slow the growth of tumor cells that express receptors for epidermal growth factor. Immunex had signed an agreement in 2000 to co-develop this drug with Abgenix (which had engineered it), and the two companies were working on it together when Amgen acquired Immunex. Panitumumab was FDA approved in 2006 to treat colorectal cancer, and Amgen acquired Abgenix later that year to grab all of the drug’s revenues and eliminate the need to pay royalties to Abgenix on denosumab (see Prolia above). In one of the first examples of the utility of cancer biomarkers, it was found that panitumumab did not work in the 40 percent of colon cancer patients who have a mutation in a gene called k-ras.

Finally, Cell Therapeutics attempted to gain FDA approval in 2010 for its drug Pixantrone, a form of the chemotherapy agent mitoxantrone (see Novantrone above) that the company believes has fewer heart-related side effects. The drug was initially developed by Novuspharma, but Cell Therapeutics gained rights to the drug by merging with the Italian company in 2003. The drug was then brought before an FDA advisory committee, which unanimously rejected it for flunking its primary goal in a clinical trial, and for Cell Therapeutics’ inability to recruit more than 140 of the planned 320 patients. The company announced plans to resubmit its application to the FDA but never did. Cell Therapeutics did receive conditional marketing approval in 2012 for the drug in several European countries for patients with multiply relapsed or aggressive non-Hodgkin lymphoma. It is sold under the brand name Pixuvri. The conditional approval means that Cell Therapeutics is required to complete additional clinical trials to clearly prove the drug’s safety and efficacy. If it does not reach this milestone, the drug’s marketing approval may be rescinded.

Other Drugs Bought and Sold by Seattle Based Biotechs, But Not Developed Here

Cell Therapeutics acquired arsenic trioxide (Trisenox) by purchasing PolaRx in 2000. The drug was approved that same year to treat the relatively rare disease acute promyelocytic leukemia; there are only about 1,000 to 1,500 cases in the U.S. per year. Cell Therapeutics wound up selling the drug to Cephalon in 2005. This made sense since it was reported that the company spent $100 million on

Author: Stewart Lyman

Stewart Lyman is Owner and Manager of Lyman BioPharma Consulting LLC in Seattle. He provides advice to biotechnology and pharmaceutical companies as well as academic researchers and venture capital firms. Previously, he spent 14 years as a scientist at Immunex prior to its acquisition by Amgen.