By Mary Welch

Algos Pharmaceutical Corp. received a "not approvable" letter for MorphiDex, a pain-management drug, causing the company's stock to tumble 59 percent.

Algos's stock (NASDAQ:ALGO) closed Tuesday at $9.937, down $14.312.

"We are disappointed but absolutely committed to working with the FDA to get this drug to the American people," said John Lyle, president and chief executive officer at Algos "MorphiDex is a drug that clearly helps people and there is a need for it."

According to Lyle, the FDA raised some issues specifically related to the clinical trials, its toxicology models and a high-dose pharmacokinetic study."

"I think that these are statistical issues and we believe our NDA [new drug application] filing is defensible and we are prepared to do it as quickly as possible," Lyle said. "We believe we have very strong statistical data. Every study showed that, without exception, patients preferred MorphiDex to morphine or any other analgesic. Not only that, they didn't have to escalate their dose over time, which is important when dealing with morphine. We will do whatever we have to in order to get this drug approved."

The company will have an informal meeting with the FDA next month.

"We will attempt to resolve the issues in September, but we are also ready to meet with an advisory committee that is scheduled for December. Not only do we have complete faith in this drug, but it is important to note that we have the financial resources necessary to fully support a resubmission of an NDA and even additional trials. A study of this sort could be done relatively quickly."

The company said it has more than $40 million in cash. Last November, it raised $25 million in a private placement aimed at funding the commercializing of MorphiDex. (See BioWorld Today, Nov. 11, 1998, p. 1.)

MorphiDex, and the other compounds in the company's pipeline, involve combinations of existing analgesics and anesthetics with N-methyl-D-aspartate (NMDA) receptor antagonists, targeting various degrees of pain.

MorphiDex, for instance, is a capsule drug containing equal parts of morphine and the NMDA-receptor antagonist dextromethorpan. The Neptune, N.J.-based company submitted an NDA for MorphiDex in August 1998 for the treatment of moderate to severe cancer pain.

The company conducted two Phase III trials. The first trial involved patients taking MorphiDex and morphine. After 30 days, patients on MorphiDex took significantly less drug and, unlike their morphine-taking counterparts, didn't have to escalate the dosage. The second double-blind trial compared pain relief and patient satisfaction for MorphiDex and morphine. After two weeks, the 250 chronic pain sufferers who converted from their previous opiate rated MorphiDex significantly superior.

"In one trial, patients on morphine ended up taking about 161 milligrams of morphine a day, while patients on MorphiDex were only taking about 80 milligrams," Lyle said.

In addition, the company has conducted a year-long open-label study with hundreds of patients. Only about 15 percent of all patients taking morphine or other analgesic drugs rated their pain satisfaction level as very good or excellent, Lyle said. "With patients taking MorphiDex for up to a year, 63 percent say their satisfaction was very good to excellent, with another 33 percent rating it good. That's 96 percent saying MorphiDex was good, very good or excellent. That's why I have complete faith in this drug. Patients keep telling us that it's the best pain management therapy they've every received with fewer side effects and an overall better quality of life."

The company has another product, HydrocoDex, a combination of the narcotic hydrocodone and dextromethorphan, expected to be in Phase III trials this year, with a NDA filing in mid-2000. HydrocoDex targets patients with less severe pain.

A third product, OxycoDex, is in late Phase II trials for moderate pain, with an NDA filing scheduled for late 2000 or early 2001. A fourth unnamed neuropathic pain capsule is in early Phase II studies.