Sandoz Biosimilar to Enbrel Gets FDA Support Ahead of Panel

FDA said in briefing documents ahead of a July 13, 2016 meeting that Sandoz’s biosimilar GP2015 has “no clinically meaningful differences” with the US-licensed and EU-licensed versions of Enbrel (etanercept) in terms of safety, purity, and potency. It also stated that a transition from Enbrel to GP2015 during the study “would support the safety of the clinical scenario where non-treatment naïve patients undergo a single transition to GP2015.”

Importantly, Sandoz included in its data submission to FDA an “innovative study design,” one that implies the company may be filing for an interchangeability status for its biosimilar in the future. The design featured multiple switches within the 52-week trial to evaluate the effect of switching between the innovator and biosimilar molecules. In two separate treatment arms, patients switched therapies after week 12, switched back to the original treatment after week 18, and switched a third time back to the alternate treatment regimen after week 24. One arm had patients switching back and forth from Enbrel (with GP2015 in between), and the other had patients switching back and forth from GP2015 with Enbrel in between. The company’s findings were that “switching does not have negative implications for safety, considering also incidences and severity of TEAEs [treatment-emergent adverse events], laboratory values, vital signs, and physical examination findings."

Sandoz’s biosimilar will go before an FDA advisory committee on July 13, and if it is eventually approved (FDA has a deadline of August 2 to decide, according to Evercore ISI analyst Mark Shoenebaum), it could launch as early as February 2017. The launch would be what is known as an "at risk" launch, however, as it falls before the patent period for Enbrel expires. Although many of the molecule patents have already expired for Enbrel, there are two patents that may constrain biosimilar entry in the United States until at least 2029, according to statistics from IMS. Patent protection for Enbrel has expired in the European, Canadian, and Australian markets, however.

The two patents in question (US8,063,182 [‘182] and US8,163,522 [‘522]) were not issued until 2011 and 2012, respectively, and Sandoz tried and failed to challenge the validity of these patents in June 2013. Sandoz claimed that its version of Enbrel did not infringe on the patents in question and they also claimed that these two patents were unenforceable.

Wednesday's committee of outside experts will discuss whether Sandoz has presented enough evidence to ensure that there are no clinically meaningful differences between Enbrel and GP2015 in Enbrel's five indications. It is likely that the committee will also address the switching component of the findings and assess the potential impact of alternating treatment with GP2015 and Enbrel.

Amgen reported global sales for Enbrel as US $5.4 billion for 2015, up 14% from 2014. Sales of Enbrel represent a quarter of the company's total sales. Not counting potential biosimilars, competitors for market share currently include Remicade, Humira, and Stelara.

Source: FDA