Pfizer-Dr Reddy’s tussle may force US to amend drug law

Gireesh Chandra Prasad G I - Mumbai

The cliff-hanger patent combat between Pfizer Inc. and Dr Reddy’s Laboratories (DRL) is likely to force Washington to amend a controversial provision in the US Federal Food, Drugs and Cosmetics Act, which the Hyderabad-based generics drug-maker applied to get marketing approval for a sister drug of Pfizer’s patented hypertension blockbuster Norvasc.

The interpretation of a grey area in the drug law by the US Court of Appeals for the Federal Circuit (CAFC), which will shortly decide on Pfizer’s patent infringement suit against DRL, will have to be incorporated in the Act, CAFC Judge Randall R Rader told Express Pharma Pulse (EPP) during a recent visit to this city.

He said the court’s interpretation would be binding on all future decisions by regulatory entities of the US government such as the FDA and the Patent and Trademark Office. Judge Randall R Rader, was also one of the chisellers of the Hatch-Waxman Act, which Pfizer owes for the patent term extension (PTE) on Norvasc (amlodipine besylate).

Pfizer alleged the FDA relied on the safety and efficacy data of Pfizer’s patent-protected US dollar two-billion-a year drug for granting final marketing nod to Dr Reddy’s version amlodipine maleate, following which the FDA decided to review the application to determine that DRL’s product has been shown to be safe and effective based on data from ‘‘appropriate sources.’’

In the crux of the FDA’s approval, is an apparent contradiction between its interpretation of the scope of Pfizer’s patent for deciding on the infringement aspect and that for determining the product’s safety and efficacy.

‘‘A generic product cannot expect a premium over the price of its counterparts as it does not have any therapeutic edge over them. Dr Reddy’s did not make an Abbreviated New Drug Application under section 505 j (as a generic) but made a New Drug Application under section 505 b (2), seemingly to claim a status above generics. This section provides for marketing approval without own safety and efficacy data or the right of reference to an approved product’s data, under certain conditions,’’ New Jersey-based patent attorney Mark Pohl, Esq told EPP on the sidelines of a workshop in the city last week.

One of the conditions, which triggers a patent infringement suit from the innovator is a certification by the second applicant that it believes the alternative does not infringe upon the pioneer’s patent or that the patent itself is invalid.

DRL claimed its amlodipine maleate is not covered by the patent term extension on Norvasc which applies only to amlodipine besylate, unlike the original ’909 patent on the molecule which encompasses similar products as well.

According to experts with US-based Coudert Brother’s LLP’s IP group, while hearing, the court seemed to find it difficult to reconcile how DRL’s amlodipine maleate could fall outside the scope of Pfizer’s patent for Norvasc (amlodipine besylate) during its patent term extension, but at the same time DRL could rely on Norvasc data to support the FDA approval. Non-infringement implies DRL’s product is distinct from Pfizer’s which makes it difficult for DRL to rely on the latter to establish the ’non-infringing’ product’s safety and efficacy.

This seems a fragile area in the Act, which probably has to be set right, said Pohl.

A patent counsel for the US arm of an Indian pharma multinational, who was present at the CAFC hearing on the case, told EPP that Pfizer initially approached the USFDA with amlodipine maleate, but later switched to amlodipine besylate following some inquiries by the Administration. He said it appears Dr Reddy’s has depended on the safety and efficacy data Pfizer provided earlier with the FDA for amlodipine maleate which implies DRL’s non-reliance on the proprietary data of Pfizer’s marketed product - amlodipine besylate.

The US FDA’s letter to DRL on the re-evaluation lays emphasis on ‘‘proper sources.’’Mounting healthcare cost has been a contentious issue in the US and a pet subject for politicians. When asked if section 505 b (2) which did not require Dr Reddy’s to produce its own data or even a right to reference, was a socially relevant but legally unsustainable one, Judge Rader said it was not proper to go into the details of this case now as it was subjudice.

When asked the same question, Mark Pohl said a socio-economic conflict is inherent in section 505 (b)(2). Interestingly, the USA acquired this ‘‘common law’’ British legal system as, like India, it used to be a British colony, he added.

The Hatch Waxman Act provides for a patent term extension based on the time the USFDA takes to review an innovator’s new drug application. Attorneys believe while the USFDA reviews the propriety of its probable reliance on the initial data Pfizer submitted for amlodipine maleate before switching to amlodipine besylate, the court would interpret the scope of this patent extension as to whether it covers near identical formulations where the only difference between the pioneer and the follower is the salt or ester form of the active ingredient.

According to Pohl, the USFDA is now trying to cover its rear. An amendment to the Federal Food, Drugs and Cosmetics Act will not come through that easily, particularly, in an election-year, said Judge Rader. The industry or the consumers have to contact their senators, make a proposal, to be followed by a debate in the Congress, its passage and finally, the presidential signature, explained Stephen C Durant, attorney at law with San Francisco-based Morrison & Forester.

When pointed out that Democrat front-runner John Kerry had gone on record saying if he ascends the White House chair, he wouldn’t mind taking on big pharmaceutical corporations to bring down healthcare cost, Durant said patents is too complex to be a campaign issue. It has to be something simple for commoners to understand.

Patent counsel for Ranbaxy Pharmaceuticals Inc George E Heibel told EPP that curtailing patent rights and bringing down drug costs would be tough for any politician. William Jefferson Clinton could not do it in his eight years of presidency although it was one of his priorities.

Meanwhile, Dr Reddy’s has fired another shot. It has filed an ANDA for Pfizer’s marketed product, amlodipine besylate, triggering another infringement suit at the New York district court, Dr Reddy’s said in a statement.