In a preliminary ruling, the U.S. Patent and Trademark Office (USPTO) has issued a double-patenting rejection on a Genentech patent indicating that the patent, awarded in 2001, covered basically the same invention as an earlier Genentech patent that was set to expire next March. Genentech called the patent examiner’s action “a routine and expected next step in the reexamination procedure.” A final resolution could take months or years and the patent will remain enforceable in the meantime. The request to reexamine the patent was made in May by a Chicago lawyer but it’s not known which company or companies are represented.

The patent, known as the Cabilly patent after the lead inventor, Shmuel Cabilly, covers what Genentech calls “the ‘fundamental technology required for the artificial synthesis of antibody molecules,” which are the basis for many of the best-selling drugs produced by the biotechnology industry. Genentech gets an estimated $300 million a year in royalties on sales of drugs like Enbrel from Amgen, Remicade from Johnson & Johnson and Synagis from MedImmune. The patent claims:

1. A process for producing an immunoglobulin molecule or an immunologically functional immunoglobulin fragment comprising at least the variable domains of the immunoglobulin heavy and light chains, in a single host cell, comprising the steps of:

(i) transforming said single host cell with a first DNA sequence encoding at least the variable domain of the immunoglobulin heavy chain and a second DNA sequence encoding at least the variable domain of the immunoglobulin light chain, and

(ii) independently expressing said first DNA sequence and said second DNA sequence so that said immunoglobulin heavy and light chains are produced as separate molecules in said transformed single host cell.

For background, on March 25, 1983, Celltech filed in the United Kingdom a patent application directed to methods of making recombinant antibodies and antibody fragments, together with vectors and host cells useful in these processes. Celltech filed a related patent application in the United States, which issued as U.S. Patent No. 4,816,397 (“the Boss Patent”). On April 8, 1983, about two weeks after Celltech’s original U.K. filing, Genentech filed a United States patent application directed to similar technology, which issued as U.S. Patent No. 4,816,567 (“the Cabilly Patent”). The Boss Patent and the Cabilly Patent issued on the same day, and both were scheduled to expire on March 28, 2006.

After Celltech’s Boss Patent issued, Genentech copied the Boss Patent claims into a previously-filed Cabilly Patent continuation application. As a result, the United States Patent and Trademark Office declared an interference between Celltech’s issued Boss Patent and Genentech’s Cabilly Patent continuation application to determine who was the first to invent, and therefore which company would be entitled to a patent on, the claimed invention. Seven years after the Genentech-Celltech interference began, the Patent Office determined that Celltech’s inventors, and thus Celltech, were entitled to the patent. Why it took so long isn’t clear – it seems that neither party had sufficient incentive to expedite the process.

Genentech appealed the Patent Office decision by filing a civil action in the United States Federal District Court for the Northern District of California. Following two years of discovery, i.e., more than nine years into the dispute, the District Court denied Genentech’s motions that it was entitled to a patent on the disputed technology. In briefing those motions Genentech and Celltech each argued that the other was not entitled to a patent. Shortly after the District Court ruled on those motions, Genentech and Celltech settled their dispute by entering into an agreement which resulted in the District Court’s issuing an order directing the Patent Office (i) “to vacate the decision in [the prior interference proceeding], (ii) “to revoke and vacate [the Boss Patent],” and (iii) “to grant and issue to Genentech’s inventors … a United States patent [with the same claims as the Boss Patent].”

The USPTO ultimately revoked the Boss Patent and issued a new United States patent, U.S. Patent No. 6,331,415 to Genentech (“the New Cabilly Patent”). All the claims originally issued in the revoked Boss Patent subsequently issued in the New Cabilly Patent. As a result, while the disputed invention was originally scheduled to pass into the public domain in 2006 upon expiration of the Boss Patent, it is now owned exclusively by Genentech until 2018, which is when the New Cabilly Patent is scheduled to expire.

MedImmune is now claiming that Genentech and Celltech conspired improperly to secure for themselves, through 2018, a dominant and exclusive position in the recombinant antibody field. But, it’s too early to try to predict the outcome so it is not clear yet if companies developing recombinant antibody-based products will become free and clear of the Boss Patent and the Cabilly Patent in 2006.

Comments are closed.