Medivation Emerges With New Prostate Cancer Drug

Xconomy San Francisco — 

San Francisco-based Medivation doesn’t quite have the brand name recognition of its rivals in the world of prostate cancer drug development, but that could be starting to change, as soon as this weekend.

Medivation (NASDAQ: MDVN) has been on a big-time roll since November, when it released results from a study of 1,200 patients, called Affirm, that showed an experimental drug could extend the lives of men with terminal prostate cancer for a median time of 4.8 months compared with a placebo. Six months later, the drug is still generating buzz heading into this weekend’s big cancer drug confab, the American Society of Clinical Oncology. Investors can’t seem to get enough, as the stock has been on a truly spectacular run, climbing from a low of $14.32 in the past year to close at $85.01 a share yesterday.

While Medivation doesn’t have another earthshaking news update to provide on its drug at ASCO, it’s clear that this pill, and what it can do for prostate cancer patients, will be one of the hot topics of conversation at the big cancer meeting in Chicago. The burning question is whether Medivation and its partner Astellas Pharma can build on the early momentum, by winning FDA approval for its product enzalutamide (MDV3100), and whether it can show its drug also works for a larger group of prostate cancer patients with a less advanced form of the disease. If Medivation can do that—and most analysts are betting it will—then it will truly be on a collision course against marketed drugs from Seattle-based Dendreon (NASDAQ: DNDN) and New Brunswick, NJ-based Johnson & Johnson (NYSE: JNJ) that have shown an ability to prolong lives in the past couple of years.

Johann de Bono

Even though there is a lively ongoing debate about how aggressively to screen for prostate cancer, and whether widespread medical interventions cause more harm than good for this slow-moving malignancy, analysts still see a multi-billion dollar market emerging. About 30,000 men in the U.S. die from prostate cancer each year, according to the American Cancer Society.

“There’s an urgent need for more patients to get an improved outcome. For 50 years we had very little progress, and in the last five years, we’ve had five new agents that improve survival,” says Johann de Bono, a professor at the Institute of Cancer Research in London, and the lead investigator of the 1,200-patient study, which Medivation called Affirm. The Medivation drug is a particular standout, he says, because at least in the Affirm study, “these patients are dying but at least they are living longer, with better quality of life. These were patients with only months left to live. These results were particularly impressive because of that.”

Even though most of the key details on the Affirm study were released at a smaller ASCO conference in February, physicians were still buzzing about it earlier this month at the American Urological Association meeting in Atlanta. The study enrolled patients whose prostate cancer had spread, and no longer responded to traditional chemical castration therapies that shut off the supply of male hormones that help fuel tumor growth. The patients had also previously gotten docetaxel (Taxotere) chemotherapy, often considered the last-ditch therapy.

Despite how sick those patients were, the Medivation drug passed the study with flying colors. Patients lived a median time of 18.4 months on the drug, compared with 13.6 months on a placebo. Medivation’s product also showed it could reduce prostate-specific antigen (PSA) scores by at least half for most patients (54 percent) while that only happened for 1.5 percent of placebo patients. The drug kept tumors from spreading for 8.3 months compared with 3 months for the placebo. Medivation’s product also met the criteria for quality of life improvement in 43 percent of patients, compared with about 18 percent of the patients on placebo. All of those findings were statistically significant, meaning there’s little chance the results were a fluke.

“There is no doubt that enzalutamide (MDV3100) is the next big thing in urology,” said David Miller, president of Biotech Stock Research, in a note to clients May 22 at the end of the AUA conference. “No other drug we see comes close.”

Each of the new drugs for prostate cancer is designed to work in a different way. Dendreon’s treatment, sipuleucel-T (Provenge), is an infusion-based medicine that is supposed to stimulate a patient’s immune system to recognize prostate cancer cells and fight them. Johnson & Johnson’s abiraterone (Zytiga) is an oral pill that’s designed to interfere with the body’s synthesis of androgens—the male sex hormones that help drive growth of prostate cancer. Medivation’s drug, also an oral pill, seeks to block the binding of androgens to the androgen receptor, which is supposed to interfere with a key process that drives tumor cell growth.

Medivation got ahold of this compound by licensing it in 2005 from the lab of Charles Sawyers, the prominent cancer researcher at Memorial Sloan-Kettering Cancer Center in New York. Like many cancer drug developers, Medivation’s strategy to bring the drug to the market was to study it first in the sickest of the sick, where the need for a new therapy was greatest. But just like most any cancer drug developer, Medivation is working its way forward into patients with less severe forms of the disease. The next big test is among 1,680 patients, in a study with the rather confident title of Prevail. That study will enroll patients whose disease has spread, and which no longer responds to traditional chemical-castration therapy, but who haven’t yet gone all the way to get last-ditch chemo. This is the so-called “pre-chemo” patient population that Dendreon is attempting to serve, and the same group of patients Johnson & Johnson is hoping to reach with its drug. J&J plans to release clinical results of a 1,088-patient at the upcoming ASCO meeting, which it has said were encouraging enough to form the basis of a new application for FDA approval.

With so many drugs new to the market or close to the marketplace, it creates some interesting new possibilities. Dr. de Bono, the lead investigator of Medivation’s Affirm study, said he believes the Medivation drug should work well in combination with J&J’s treatment. By blocking androgen synthesis (J&J), and androgen uptake into cells (Medivation), the hope is to provide a more comprehensive blockade of the substances that nourish prostate tumors. “These drugs have great potential given together. [They are] very different agents that I hope will be complementary,” de Bono says.

Despite the progress in treating prostate cancer, nobody is making claims about having a cure. Tumors are wily creatures, and they often end up finding ways to resist new treatments, a process which isn’t fully understood. One of the critical next questions, de Bono says, is finding out what causes resistance. But given the progress of the past few years with the new drugs, de Bono strikes a very optimistic tone. “We haven’t cured prostate cancer, sadly, although we’re getting there,” he says.