Sanofi-Aventis U.S. LLC plans to ask a federal judge Friday to delay the first bellwether trial over breast cancer drug Taxotere, citing a U.S. Supreme Court decision that requires a “completely different approach” to federal preemption and already prompted postponement of a separate trial over nausea drug Zofran.

In an Aug. 9 motion, Sanofi attorney Douglas Moore, of New Orleans-based Irwin Fritchie Urquhart & Moore, sought a “brief continuance” of a Sept. 16 trial, the first of among 12,000 lawsuits coordinated in New Orleans federal court alleging Taxotere caused permanent hair loss, or alopecia areata.

Among his reasons were 58 pending pretrial motions, including Sanofi’s motion for summary judgment based on federal preemption, which he claimed needed more time given the U.S. Supreme Court’s intervening decision in Merck Sharp & Dohme v. Albrecht. The May 20 decision, he wrote, prompted U.S. District Judge Dennis Saylor of the District of Massachusetts in Boston to postpone the first bellwether trial over Zofran, also scheduled for Sept. 16, and vacate a portion of his ruling denying federal preemption to GlaxoSmithKline.

“This court should exercise its discretion in the same deliberate manner as Judge Saylor,” Moore wrote. “Albrecht now requires a completely different approach to the resolution of preemption in pharmaceutical cases. That approach simply cannot be accomplished on the schedule currently pending in this MDL.”

On Wednesday, U.S. District Judge Jane Milazzo of the Eastern District of Louisiana denied Sanofi’s summary judgment motion, even under the requirements set forth in Merck, but only as to Barbara Earnest, the plaintiff going to trial next month.

On the same day, plaintiffs attorneys in Taxotere opposed the continuance, stating that it was “unprecedented” given that the judge already postponed the May 13 trial once before.

“A continuance at this stage would deeply prejudice not just Ms. Earnest, but also the thousands of women who have waited years for answers,” wrote co-lead counsel Christopher Coffin, of PBC in New Orleans. “Some are ill; several have passed away. Further delay works an unacceptable denial of justice.”

“The plaintiffs’ leadership is confident that the court will deny Sanofi’s motion for continuance and keep the September 16 trial date,” wrote Coffin in an email.

Sanofi attorney Moore and three partners at Shook, Hardy & Bacon in Kansas City, Missouri—Harley Ratliff, Adrienne Byard and Kelly Bieri—did not respond to a request for comment. A Sanofi spokeswoman also declined to comment.

Shook, Hardy & Bacon represents both Sanofi and GlaxoSmithKline in the Taxotere and Zofran cases.

The Taxotere litigation is one of several in which lawyers have cited the Merck decision, at times forcing judges to reevaluate their rulings. Monsanto Co. cited the ruling in post-trial motions challenging a $2 billion Roundup verdict, as did plaintiffs in a failed petition before the Supreme Court to reinstate a $3 million verdict over a Reed Smith partner’s suicide tied to GlaxoSmithKline’s antidepressant drug Paxil.

In Merck, the Supreme Court found that the pharmaceutical manufacturer could not provide “clear evidence” that the U.S. Food and Drug Administration would have rejected a change to the warning labels on its osteoporosis drug Fosamax. The ruling also found that a judge, not a jury, should decide whether “clear evidence” existed.

Soon after the ruling, Saylor asked lawyers in the Zofran multidistrict litigation to file briefs asserting how the decision could influence his Feb. 5 summary judgment ruling denying federal preemption in more than 450 cases alleging the anti-nausea drug caused birth defects.

On July 16, Saylor vacated a portion of his summary judgment ruling, stating that the “clear evidence” facts should go before a judge. He also postponed the first bellwether trial. Taking up the defendant’s suggestions, he allowed GlaxoSmithKline to file a renewed motion for summary judgment in what the drug maker called a “textbook case for preemption.”

Saylor also asked both sides to file briefs over whether to invite the FDA to submit an amicus brief on the issue—a move that plaintiffs said they “strenuously object to”—and heard more arguments Wednesday about Merck.

Plaintiffs’ attorneys who filed the brief did not respond to a request for comment. They are Robert Jenner of Jenner Law in Baltimore; Tobias Millrood of Pogust Millrood in Conshohocken, Pennsylvania; Kimberly Baden of Motley Rice in Mount Pleasant, South Carolina; Elizabeth Graham of Grant & Eisenhofer in Wilmington, Delaware; and James Gotz, a Boston partner at Hausfeld.

GlaxoSmithKline’s attorneys at Shook, Hardy & Bacon—Jennifer Hill and Jennifer Stevenson, both in Kansas City, and firm Chairwoman Madeleine McDonough in Washington, D.C.—did not respond to a request for comment. GlaxoSmithKline spokeswoman Courtney Dysart also declined to comment.

In the Taxotere litigation, Sanofi tried to argue that the FDA refused to approve a label change about permanent hair loss. In addressing the case of Earnest, diagnosed with breast cancer in 2011, Milazzo found that Sanofi still had not provided “clear evidence” under Merck.

“Defendants have failed to demonstrate that the FDA prohibited Sanofi from using stronger language in Taxotere’s label,” Milazzo wrote. “Sanofi was not trying to alert the FDA of the uptick in reports of permanent alopecia but instead trying to expand the distribution of its drug. The references to alopecia appear tangential at best.”

Sanofi, in its motion, raised other reasons to postpone the trial. In addition to numerous motions still pending, Milazzo is overseeing “another important case” that starts Aug. 19: The public corruption criminal retrial against former Drug Enforcement Administration agent Chad Scott.

Plaintiffs attorneys, in their response, criticized Sanofi’s “twisting of this court’s words in an attempt to take advantage of the court’s dedication to managing a high profile criminal matter in parallel to this MDL and to insinuate that the court cannot manage both.”

Sanofi also cited other motions, such as its pending request to certify Milazzo’s July 9 order for interlocutory appeal denying summary judgment on causation as to the plaintiff in next month’s trial, and in another case. Sanofi had sought to adjourn the trial alongside that motion. Plaintiffs attorneys, meanwhile, have filed a motion to reconsider the same ruling, which granted summary judgment on statute of limitations grounds as to two other plaintiffs.

In addition to the continuance motion, on Friday, Milazzo plans to hear arguments over Sanofi’s certification motion.

“It is no one’s fault that this MDL is complex or that numerous significant motions remain pending before the first trial date,” Moore wrote. “The parties and the court have worked hard to significantly advance this MDL and prepare for the first bellwether trial. Notwithstanding those efforts, though, more time is needed to complete pretrial work.”