Sandoz Enbrel Copycat Next Biosimilar To Get Panel Treatment

The FDA has elected to take Sandoz Inc.'s 351(k) application for its etanercept biosimilar, which is referenced on Amgen Inc.'s tumor necrosis factor blocker Enbrel, to an advisory committee to get its advice on whether to license the product. It's only the third biosimilar to get the expert panel treatment.

While there's little insight at this point into what the FDA thinks about Sandoz Inc.'s version of Amgen Inc.'s Enbrel, it's clear, now, after regulators scheduled a July 13 advisory committee meeting the agency wants the advice of its outside experts before making a decision on whether to permit the etanercept biosimilar to enter the US market.

The agency has only convened its advisory panels twice before to examine so-called 351(k) applications for biosimilars and both of those products – Sandoz's Zarxio (filgrastim-sndz), a version of Amgen's Neupogen, and Celltrion Inc.'s and Pfizer Inc.'s Inflectra (infliximab-dyyb), which is referenced on Johnson & Johnson unit Janssen's Remicade – were overwhelmingly embraced by the respective committees (Also see "Novartis/Sandoz biosimilar 1st to win FDA panel backing" – Scrip, 08 Jan, 2015, "FDA's 1st biosimilar adcomm: a lovefest" – Scrip, 08 Jan, 2015, and "Panel Favors Celltrion Biosimilar; Skeptical On Cost Savings" – Scrip, 10 Feb, 2016).

Both of those biosimilars also have since been approved (Also see "Novartis/Sandoz make history with 1st US biosimilar Zarxio" – Scrip, 06 Mar, 2015, and "Celltrion/Pfizer Inflectra Second US Biosimilar; Many Firsts" – Scrip, 06 Apr, 2016).

Now comes Sandoz's application for GP2015, its etanercept biosimilar, which will be reviewed by the FDA's Arthritis Advisory Committee – the same panel that scrutinized Celltrion's and Pfizer's Inflectra in February (Also see "Sandoz 2nd Biosimilar At FDA; Seeks Slice Of Enbrel Sales" – Scrip, 02 Oct, 2015).

Analysts at Informa Pharma Intelligence's Biomedtracker, an affiliate of Scrip, have put the chances of GP2015 winning the FDA's blessing at 87%.

Like Inflectra, Sandoz's GP2015 is a tumor necrosis factor blocker, which is seeking to compete in some of the same indications as the Celltrion/Pfizer biosimilar.

Inflectra was licensed by the FDA in the US for rheumatoid arthritis (RA), active ankylosing spondylitis (AS), psoriatic arthritis (PsA), plaque psoriasis (PsO), Crohn's disease in adults and pediatric patients and ulcerative colitis (UC) in adults.

The only indication that Remicade carries that Inflectra doesn't is use for pediatric UC, and that's because Janssen's branded medicine holds orphan drug exclusivity on that indication until Sept. 23, 2018.

Sandoz is seeking approval to market its etanercept biosimilar as a treatment for RA, polyarticular juvenile idiopathic arthritis, PsA, AS and PsO – the same indications for which Enbrel is licensed by the FDA.

Lawsuits, Lawsuits, Lawsuits

And like Inflectra and Zarxio, Sandoz's GP2015 is caught up in a legal battle (Also see "Lawsuit: Sandoz Copycat Piggybacks Enbrel, Ducks Duties" – Scrip, 01 Mar, 2016).

Through its lawsuit over Zarxio, Amgen managed to keep the filgrastim biosimilar from entering the US market until six months after its March 2015 approval – a legal dispute for which the US Supreme Court currently is mulling over whether to hear (Also see "1st U.S. Biosimilar Arrives: Zarxio Launches; Legal Saga Ongoing" – Scrip, 03 Sep, 2015, and "Amgen: Zarxio Lawsuit 'Poor Vehicle' To Interpret BPCIA" – Scrip, 24 Mar, 2016).

And even though Inflectra was licensed in April, Janssen succeeded in getting Celltrion and Pfizer to hold off marketing the product until at least mid-September, absent certain circumstances, under a recent agreement in their current legal fight (Also see "Celltrion/Pfizer Agree To Wait For Mid-September Inflectra Launch" – Scrip, 08 Jun, 2016).

Washington lawyer Bill James, a partner at Goodwin Procter LLP, told Scrip the district judge in the Enbrel dispute on June 1 set out a schedule for certain filing deadlines in the case, with disclosures set to be exchanged by no later than June 15 – the same day by which they must disclose infringement contentions, asserted claims and any accompanying documents.

James noted the judge has scheduled a status conference for June 16 – declaring the attorneys for both sides should be prepared to discuss settlement at each of the conferences.

James said he anticipated lawyers for both sides to be in attendance at the July 13 FDA's Arthritis Advisory Committee meeting, watching to see what might possibly come out that might be useful in the ongoing litigation.

As for Amgen's lawsuit against Sandoz involving Zarxio – which is really over the interpretation of the Biologics Price Competition and Innovation Act – James said the Supreme Court is set to consider the companies' petitions at a June 16 conference, with a decision on whether to hear the case expected on June 20.

If the justices are inclined to grant certiorari, they might relist the case one more time and issue a decision on June 27, he said.

What About Pegfilgrastim Apps?

Long before the FDA accepted Sandoz's 351(k) for its etanercept product in October 2015, the agency agreed in December 2014 to examine Apotex Inc.'s application for its version of pegfilgrastim, which is referenced on Amgen's Neulasta (Also see "Apotex biosimilar of Amgen's Neulasta under FDA review" – Scrip, 18 Dec, 2014.)

But the FDA hasn't scheduled a panel hearing on that application – currently in a legal battle of its own, with a decision pending from the US Court of Appeals for the Federal Circuit – nor has the agency set a committee meeting for Sandoz's pegfilgrastim 351(k), accepted for review this past November (Also see "Court Probes Rationale Of Biosimilars' 180-Day Notice" – Scrip, 05 Apr, 2016, and "Sandoz Neulasta Biosimilar Under FDA Review; Where's Apotex?" – Scrip, 19 Nov, 2015).

First Panel Doesn't Mean First Reviewed

Leah Christl, associate director for therapeutic biologics at the FDA, has emphasized the agency is anticipating that at least one biosimilar application per referenced product would go before a panel, but it doesn't necessarily need to be the first one accepted and under review.

"There may be product-specific issues, so a program may warrant a discussion," she said at a forum in Washington this past fall hosted by the analysis firm Prevision Policy and patient advocacy group Friends of Cancer Research (Also see "US Capitol Capsule: Don't Make Assumptions On Biosimilars Actions, FDA Official Warns" – Scrip, 16 Nov, 2015).

Christl also pointed out "it's not a one and done type of thing, necessarily," so there's the possibility Samsung Bioepis Co. Ltd.'s and Merck & Co. Inc.'s infliximab also could get a panel treatment (Also see "Samsung/Merck Closer To US Biosimilars Market; Infliximab App Accepted" – Scrip, 25 May 2016).

Given the FDA is forbidden to disclose applications under review, there's the possibility there may be other etanercept biosimilar 351(k)s before the agency from companies that have not revealed their submissions.

Goodwin Procter's James pointed out there may be specific issues with Sandoz's Enbrel application the FDA has decided merit input from its advisers, and that's why the agency has elected to review it rather than wait for the next etanercept biosimilar.

"We don't know if this is to drill down on one regulatory issue or others that may impact what is in future filings," he said.