US FDA's Biosimilars Chief Leah Christl Plans Departure

A departure date has yet to be determined for the associate director of therapeutic biologics, who helped negotiate and implement the biosimilar user fee program.

The US FDA is preparing for the departure of the head of its biosimilars program, Leah Christl, who has helped shape the pathway since its infancy.

Christl, associate director of therapeutic biologics in the Office of New Drugs, is expected to leave the agency soon, although a departure date has not been determined.

Christl has been in charge of FDA's biosimilars review and development programs for more than eight years and oversaw the implementation of the biosimilars user fee program, which included FDA's first biosimilar approvals. She has been working at FDA since 2003, joining from the University of South Carolina, according to her LinkedIn profile.

FDA did not respond to questions about its plans to replace Christl once she leaves. However, the agency may already have started preparing for the move.

Joseph Franklin, associate director of the therapeutic biologics and biosimilars team, has appeared at many conferences and other public events to represent the biosimilars program in recent months. Franklin could be a prime candidate to take over the program at least temporarily. (Also see "Should A Biosimilar Sponsor Do The 'Patent Dance?' It Depends On Many Things" - Pink Sheet, 22 Aug, 2017.)

Christl also did not appear at the Oct. 10 Oncologic Drugs Advisory Committee hearing on Celltrion Inc.'s rituximab biosimilar. Sue Lim, director of the scientific review staff for the OND therapeutic biologics and biosimilars staff, represented the group. (Also see "Celltrion’s Rituximab Biosimilar Has Easy US FDA Panel Ride Despite Questions About Narrow Label" - Pink Sheet, 10 Oct, 2018.)

Christl had been a staple at biosimilar advisory committee meetings, often explaining the difference between the approval requirements for biosimilars and new drugs. (Also see "Biosimilar Advisory Committee Reviews: Necessity Or Nuisance?" - Pink Sheet, 20 Jul, 2016.)

Christl's potential post-FDA landing spots could include active biosimilar sponsors, such as Sandoz Inc., Amgen Inc., and Pfizer Inc.. All of them have multiple approvals and/or applications in development and would benefit from Christl's scientific and regulatory expertise.

A consulting position also is a possibility, a route former OND Director John Jenkins decided to take following his retirement in early 2017. (Also see "Jenkins’ Exit Interview: He’ll Miss Insider Status Upon FDA Departure" - Pink Sheet, 13 Dec, 2016.)

Christl Became FDA Face For Biosimilars

FDA is more than six years into the biosimilar user fee era, which created a steady external funding stream for FDA to review applications and create infrastructure for guidance and scientific development.

Christl was among the FDA officials who negotiated the initial biosimilar user fee agreement with industry, as well as its renewal. (Also see "Two Out Of Three Ain't Bad: Biosimilar User Fee Talks Completed" - Pink Sheet, 20 Jun, 2016.) She also appeared in videos for patients and the public explaining the biosimilars development and approval processes, as well as interchangeability.

And as FDA developed biosimilar policy, Christl largely has been the agency's ambassador to industry, both interpreting and explaining agency stances.

When FDA withdrew its guidance on biosimilar statistical approaches for showing analytical similarity in 2018, Christl addressed the resulting uncertainty, saying sponsors will receive more application-specific advice and that many of the tenets of the document were still valid. (Also see "With Biosimilar Statistical Guidance Withdrawn, Expect Sponsor-Specific Advice, FDA's Christl Says" - Pink Sheet, 25 Jun, 2018.)

Christl also has engaged in the debate over FDA's controversial plan to add a suffix to the non-proprietary names of all biosimilars and brand biologics, which remains under review. (Also see "Suffix Smackdown: Gottlieb Calls Issue 'Red Herring' For Biosimilars" - Pink Sheet, 18 Jul, 2018.)

In addition, she explained the agency's decision not to convene an advisory committee for a first-in-class biosimilar after it approved Mylan NV and Biocon Ltd.'s Fulphila (pegfilgrastim-jmdb). (Also see "US FDA's Biosimilar Advisory Committee Policy Evolves" - Pink Sheet, 8 Jul, 2018.)

And Christl was bullish on the emergence of interchangeable biosimilars, remarking in 2017 that she expected the products to begin reaching the market in two years. (Also see "Best Of Biosimilar Agreement: FDA, Industry Tout Written Response, Pre-Submission Meeting" - Pink Sheet, 29 Jun, 2017.)

Departure of Agency Experience Continues

Turnover among the senior leadership ranks is not uncommon at FDA, and agency officials are recruiting and grooming the next generation to step into the openings.

Principal Deputy Commissioner Rachel Sherman recently announced she will retire this month. FDA already has found a replacement, Amy Abernethy of Flatiron Health Inc.. (Also see "US FDA Taps Abernethy As Principal Deputy Commissioner; Health IT Exec Brings “Real-World” Expertise" - Pink Sheet, 17 Dec, 2018.)

OND also has a new head; Peter Stein also was promoted to director after a nearly two-year search following Jenkins' retirement. (Also see "Peter Stein Takes Short Path To Director Of US FDA Drug Office " - Pink Sheet, 9 Dec, 2018.)

More new leaders likely will emerge soon, as the pending reorganization of OND will create many new offices and divisions. (Also see "CDER Recruitment Wins Begin Outnumbering Losses" - Pink Sheet, 26 Nov, 2018.)

Christl was expected to head the Office of Therapeutic Biologics and Biosimilars, which was included in the proposed OND structure.  (Also see "Office Of New Drugs Reorg Is Bigger Than Expected: US FDA Adds 11 Review Divisions " - Pink Sheet, 4 Jun, 2018.)