AbbVie and Humira patent thicket

AbbVie's original Humira biotherapeutic patent expired in 2016. So how did they expand their patent defenses to 2034 and beyond?

AbbVie has made over $100 billion off of Humira, a monoclonal antibody (biotherapeutic) directed against the naturally occurring human TNFα cytokine that causes inflammation.

The original Humira patent was Salfeld, US patent 6,090,382, based on a February 1996 application, that issued in July 2000. Such patents normally expire 20 years after filing. However, the Hatch-Waxman act allows pharmaceutical patents to be extended to make up for any FDA approval delays. In this case, an IND (Investigational New Drug) application became effective in April 1998, and after about four years of review, the FDA approved Humira in December 2002. So, a few additional years of lifetime extension is to be expected.

Well and good. Pharmaceutical companies can spend a billion or more getting drugs developed and approved. Without adequate financial incentives, we will not get many new drugs.

However, sometimes the patent legal system can “jump the shark”. This is particularly the case for biopharmaceuticals. These molecules are so large and complex that even minor variations in processing or manufacture can cause unpredictable effects. If you look at a biopharmaceutical cross-eyed, do you have to then repeat years of clinical trials again?

Maybe, maybe not. But it is a great opportunity for legal fun and games. Why not seek to patent every aspect of the manufacturing process? Why not drag these patents out for years? Since the manufacturing process is usually highly proprietary, who is to say that a particular manufacturing process is new? Perhaps it was a part of the original manufacturing process, and the resulting products have been sold for years. Does the one-year on-sale patent bar still apply? Who knows!

In any event, AbbVie filed hundreds of subsequent patents. These are listed in the FDA Purple Book. Let’s rather randomly look at Labkovsky, US 9,550,826. This was based on a 2014 application, and it won’t expire until late 2034.

Labkovsky covers the Fc portion of an antibody — specifically Humira. This claims glycosylated (a type of sugar molecule) versions. Antibodies are well known to be glycosylated, and likely the original version of Humira also had glycosylated Fc portions. To be fair, AbbVie filed an incredible number of prior art documents for the examiner to consider. The citations alone run to 19+ pages of small type in the published patent!

Did the USPTO examiner ask difficult questions about this? Maybe at least inquire about any double patenting issues? Nope! The examiner promptly issued a notice of allowance without any questions. AbbVie then filed some additional disclosures which were also accepted without question, and the patent issued.

Ugh. I don’t mean to imply that AbbVie is at fault. If they adequately explained the background art, then they may have played the game according to the rules. But in my opinion, the USPTO examiner could have easily been overwhelmed by the complexity. Perhaps the examiner simply took AbbVie’s word for it.

The patent rules need some tweaking here. Perhaps the USPTO should place a limit on the number of citations an applicant can file? Expecting an examiner to seriously consider this number of citations is unreasonable. This is the patent version of a stack overflow error.