The US Food and Drug Administration (FDA) on Thursday released 38 new and revised draft guidance documents for drugmakers looking to begin research and development for new generics, including for some blockbuster drugs that have not yet lost patent protection.

The new draft documents focus on what types of bioequivalence (BE) studies may need to be conducted to obtain abbreviated new drug application (ANDA) approval. Each document also contains information on what analytes should be measured, what dissolution test methods should be used and sampling times.

The latest bunch of drafts and revisions follows FDA’s release in January of product-specific recommendations for 31 different active pharmaceutical ingredients (APIs) linked to new generics and revised recommendations for 11 APIs, as well as the release of 38 draft guidances for APIs in April.

All of the draft guidance documents on BE studies are being released as part of FDA’s process to develop and disseminate product-specific BE recommendations and provide an opportunity for the public to consider and comment on those recommendations within 60 days of their announcement in the Federal Register. For a complete history of previously published Federal Register notices related to product-specific BE recommendations, go to http://www.regulations.gov and enter Docket No. FDA-2007-D-0369. 

New Guidance

Among the latest round of new draft guidance, FDA is offering new insight on how to develop generics for Novartis’ blockbuster cancer and transplant treatment Afinitor (everolimus), which does not have any generic competitors and was first approved by FDA in 2009.

Perhaps the most surprising new draft guidance document is one for companies looking to develop generic versions of (the now infamous) Valeant Pharmaceuticals’ female libido drug Addyi (flibanserin), which Valeant purchased from Sprout Pharmaceuticals for $1 billion in August 2015 before deciding in April to eliminate the drug’s sales force. What’s surprising is that draft guidance means that FDA believes there’s a market for a generic version of a brand-name drug that has failed.

Also included is one draft guidance to help generic companies develop versions of AbbVie’s hepatitis C blockbuster Viekira Pak (Ombitasvir; Paritaprevir; Ritonavir), which was approved in 2014 and is forecast to earn about $2 billion this year.

In addition, FDA released draft guidance for those looking to develop: 

• Generic versions of Genentech’s cancer treatment Cotellic (cobimetinib), which was first approved in November 2015;
• Topical hydrocortisone, which has numerous generic versions;
• The anesthetic propofol, which also already has generic versions;
• The transplant drug tacrolimus, which first saw generics launched in 2009;
• The orphan drug selexipag, known by its brand name as Uptravi, which was first approved in December 2015 to treat pulmonary arterial hypertension;
• The decongestant pseudoephedrine hydrochloride, which is known better as Sudafed;
• The antipsychotic Vraylar, also known as cariprazine hydrochloride, which was first approved in September 2015;
• The topical lotion amcinonide;
• Empagliflozin and metformin hydrochloride, Eli Lilly’s type 2 diabetes drug Synjardy, which was first approved in August 2015;
• Fluocinonide (as a gel and ointment);
• AstraZeneca’s gout treatment lesinurad, first approved in December 2015;
• The nonsteroidal anti-inflammatory drug meloxicam;
• A treatment for severe bleeding from the uterus after childbirth, known as methylergonovine maleate; and
• The dermatological cream prednicarbate.

Nineteen other revised bioequivalence recommendations are also included in what was released on Thursday.

Product-Specific Recommendations for Generic Drug Development