The market return of the antiparasitic Sentinel (milbemycin oxime/lufenuron) and Deramaxx (deracoxib), an arthritis pain medication, are on the horizon after a nine-month production delay. Officials with Novartis Animal Health have not issued firm distribution dates.

News about Sentinel and Deramaxx comes via an Aug. 1 letter to practitioners in which Novartis officials announce that they’re restarting manufacturing processes for both products.

To veterinarians awaiting the release of backordered Novartis drugs, the report is encouraging. Practitioners have been without several veterinary specific drugs made by Novartis since last December when the company shut down its plant in Lincoln, Neb. The closure followed several scathing inspection reports by the U.S. Food and Drug Administration (FDA) that identified manufacturing mishaps involving pill mixups and sloppy quality control procedures.

In January, Novartis warned consumers that chipped or broken pills might be found in over-the-counter drugs such as Bufferin, Excedrin, Gas-X Prevention and NoDoz, all made at the Lincoln plant. At the same time, veterinarians were warned of possible tablet mixups in bottles of the anti-anxiety medication Clomicalm (clomipramine hydrochloride), also made at the Lincoln site.

Novartis now says it’s readying to reopen the Lincoln manufacturing facility. During a recent teleconference with investors, Chief Executive Officer Joseph Jimenez shed light on the plant’s operational status, revealing that at least some of the company’s backordered medications might be in supply this fall. During the meeting, Novartis's Brian McNamara, OTC division head, stated that sales of three Novartis brand-name products — Sentinel, Lamisil and Excedrin — generate 30 percent of overall sales coming from the Lincoln facility.

“Our quality remediation activities are progressing at our Lincoln, Neb., manufacturing site,” Jimenez said. “We've resumed production, and we've initiated product validation for Excedrin in over-the-counter drugs and for Sentinel in Animal Health. And we expect to begin shipments of limited portfolio in the fourth quarter."

Novartis officials cited a 24-percent drop in second-quarter Consumer Health division revenues, owing to the suspended production at the Lincoln manufacturing plant. Novartis Consumer Health includes the company’s animal health division.

Interceptor, which also generates substantial sales for Novartis and is a casualty of the Lincoln plant's closure, was not mentioned in the company's financial reports. Evidence suggests, however, that Novartis might not reinstate production of the heartworm preventative in favor of manufacturing a new version of it. In August, the FDA approved Interceptor Spectrum Chewable Tablets. The new formulation adds praziquantel, an anthelmintic that controls tapeworms, to Interceptor’s original active ingredient, milbemycin oxime, which is used to kill heartworms and control disease caused by roundworms, hookworms and certain whipworms.

Novartis also has added praziquantel to Sentinel. The FDA approved Sentinel Spectrum in January and granted the company market exclusivity of the drug through Dec. 8, 2014.

The new formulations are not yet available in the United States. Novartis spokesman Joseph Burkett was not forthcoming about the status of Spectrum versions and whether they’d replace original Sentinel and Interceptor formulations.

“As a matter of policy, Novartis Animal Health considers its research pipeline and brand strategies to be proprietary information,” he said by email. “In that regard, I can’t provide you with additional information."

Dr. Steven Hornstein, a solo practitioner in Monroe Township, N.J., has turned to other, more costly anti-worm medications since Interceptor’s absence from the market. He’d prefer to go back to it.

“I wouldn’t be surprised if this new version comes out first and replaces Interceptor, but I’d like to know what’s happening,” he said. “If Interceptor doesn’t come back, from a cost standpoint, that may be problematic.”

In the meantime, Novartis has issued rebates to pet owners, inviting them to “save big” when Sentinel and Interceptor return to market. The amount of the cost savings is not specified. Hornstein assumes the rebates will be honored in the wake of new product formulations. Company officials did not respond to a request to clarify the rebate's parameters.

Dr. Kate McDuffee of Dahlonega, Ga., is aggravated by the uncertainty surrounding Novartis drug supplies. She relies on Interceptor to control whipworm infestations in her patients.

"The big thing that's irked me has been a lack of clear communication from this company," she said. "It's like the animal health division isn't important to them."