Nastech Pharmaceutical Co. Inc.'s reformulated treatment for vitamin B-12 deficiency, Nascobal (cyanocobalamin) Nasal Spray, received an approvable letter from the FDA.

The product stands to receive outright approval following resolution of third-party manufacturing issues. Specifically, the agency needs to inspect a supplier's B-12 raw material manufacturing facility and finalize product labeling. There were no FDA requirements for additional work related to manufacturing, preclinical or clinical studies.

"The shorter the better, and this is a short approvable letter," Gordon Brandt, Nastech's executive vice president of clinical research and medical affairs, told BioWorld Today. "This is not [related to] the inspection of a Nastech facility, but it's an inspection of the raw material supplier's facility. We expect the inspection to be completed in the very near future, and then, per FDA guidelines, there is a 45-day clock that will start thereafter."

The Bothell, Wash.-based nasal drug delivery firm developed the product as an alternative to Nascobal Nasal Gel, which has been marketed in the U.S. since 1997 for various vitamin B-12 deficiencies, which can occur in patients with pernicious anemia, Crohn's disease, HIV/AIDS and multiple sclerosis, as well as other malabsorptive conditions.

A new drug application for the nasal spray was filed late last year. (See BioWorld Today, Dec. 31, 2003.)

Worldwide marketing rights to both the nasal spray and gel products are controlled by Questcor Pharmaceuticals Inc., of Union City, Calif., as a result of a June 2003 divestiture agreement with Nastech. That deal resulted in an up-front payment of $18.2 million to Nastech.

"The advantage of Nascobal gel is that it's easier, more convenient and more patient-friendly than going to a doctor's office to get a monthly shot of B-12," Brandt said. "It also ensures consistent levels over the course of a month, whereas after the shot you would get a big peak and then a trough that would potentially come down below therapeutic levels at the end of the month. So we see the spray as a logical evolution - the gel is more convenient than the injection, and the spray is presumably even more convenient than the gel."

Symptoms of vitamin B-12 deficiency include fatigue, weakness, sore tongue, forgetfulness, weight loss, lack of coordination and difficulty walking. Left untreated, vitamin B-12 deficiency can lead to anemia, intestinal problems and irreversible nerve damage.

Questcor, which markets Nascobal Nasal Gel to neurologists and gastroenterologists, will make product-launch decisions following final FDA approval. That event would trigger a $2 million milestone payment to Nastech, which is not eligible to receive royalties on Nascobal gel or spray sales, but under terms of a supply agreement, receives manufacturing revenue for its production tasks. It will supply the nasal spray product to Questcor, as it already does with the nasal gel product. (See BioWorld Today, June 18, 2003.)

Nascobal Nasal Gel, which is rubbed on the inside of the nose, is the only marketed product that employs Nastech's technology. Other programs primarily are focused on nasal delivery of peptides and proteins.

A recently reported deal with Merck & Co. Inc., of Whitehouse Station, N.J., which could be worth up to $346 million to Nastech, is aimed at obesity through the delivery of PYY. The company also is exploring the use of parathyroid hormone for osteoporosis and interferon beta for multiple sclerosis.

On Monday, Nastech's stock (NASDAQ:NSTK) gained 18 cents to close at $13.33.