For the second time this term, the U.S. Supreme Court has asked for the solicitor general's views on a case involving Section 101 patent eligibility.

The high court issued a series of four controversial decisions on patent eligibility between 2010 and 2014, but has been silent since. The decisions have led to the rejection of thousands of patents, mostly in the software area but quite a few in the biopharma area as well.

“I think two CVSGs suggests that the court is concerned about the way the doctrine is developing at the Federal Circuit and the broader impact” that its decisions have had, particularly Mayo Collaborative v. Prometheus Laboratories and CLS Bank v. Alice, Emory University IP law professor Timothy Holbrook said.

Monday's request came in Hikma Pharmaceuticals USA v. Vanda Pharmaceuticals. The issue is whether the application of a law of nature as a method of medical treatment—in this case adjusting the dosage of a potentially toxic medicine based on the patient's genotype—is eligible for a patent. The Federal Circuit ruled that it is eligible in a divided decision.

The Supreme Court held more than 40 years ago that a law of nature cannot be the subject of a patent, even if that law is newly discovered. More recently, in 2012's Mayo, the justices ruled that adjusting the dose of a drug based on the level of its metabolites measured in a patient's blood could not be patented.

The biopharma industry has complained that this makes it impossible to patent some genuine medical breakthroughs, such as an innovative method for determining fetal abnormalities. Medical clinics and the generic pharmaceutical industry respond that single inventors should not be allowed to monopolize laws of nature.

Vanda argues that its 8,586,610 patent is “exactly the kind of innovation the patent laws are intended to promote.” Novartis had given up after spending millions to try to develop the drug in question, iloperidone, to treat schizophrenia. The problem has potentially fatal cardiac side effects.

Vanda bought the rights to the drug for $500,000. Vanda scientists then discovered that patients who have a genetic mutation that results in a lower-than-normal amount of a liver enzyme were at greater risk, but also could be treated effectively at a lower dosage.

The Federal Circuit found the claims not directed to a law of nature, but to “a specific method of treatment for specific patients using a specific compound at specific doses to achieve a specific outcome.”

A Winston & Strawn team led by partner Steffen Johnson petitioned for certiorari last fall on behalf of Hikma, which wants to market a competing drug. They argue that Vanda got a free pass simply by framing the natural law as a method of treatment. Hikma points to guidance the U.S. Patent and Trademark Office issued to its examiners following the decision, which says that “it is not necessary for 'method of treatment' claims that practically apply natural relationships to include nonroutine or uncon-ventional steps to be considered patent eligible.”

“As a result, diagnosis claims can now be redrafted as treatment claims that merely direct doctors to follow the natural law in administering known drugs for their known purposes—effectively rendering Mayo a dead letter,” Hikma's petition states.

Holbrook and Villanova law professor Michael Risch say that both Vanda and the earlier case that was referred to the solicitor general, HP v. Berkheimer, are at some level about the application of rules and standards.

“Berkheimer is about whether judgments are correct on the pleadings, and the 'rule' seems to be you need evidence,” Risch said. “Vanda is about whether a new treatment method is eligible. The Federal Circuit doesn't mean always in either of these cases, but it's hard to distinguish when the rules of these cases don't apply,”

Risch noted that all four of the court's recent eligibility decisions resulted in at least some patent claims being canceled. “Until the Supreme Court finally rules a patent eligible, we'll never really have peace in this area,” he said, “and so the court might be seeing if either of these two cases fit that bill.”