CDER Exclusivity Board: Barium is Not an NCE Eligible for 5-Year Exclusivity

September 5, 2018By Kurt R. Karst

We recently came into possession of a small stack of Letter Decisions issued by the Exclusivity Board in the Center for Drug Evaluation and Research – the “CDER Exclusivity Board” – and decided that a series of posts on each decision would be an entertaining way to delve into and discuss various issues that arise with both 5-year New Chemical Entity (“NCE”) exclusivity and 3-year new clinical investigation exclusivity.

By way of background, the CDER Exclusivity Board was established to “oversee certain exclusivity determinations, including whether and what type of exclusivity should be granted and the appropriate scope of exclusivity grants,” and to ensure consistency and accuracy among exclusivity determinations.  The Board has been in existence for quite some time.  While it’s been almost 6 years since FDA publicly announced, in Fall 2012, the establishment of the Board (see our previous post here), the Board had already issued decisions before then (for example, with respect to the availability of 3-year exclusivity for an NDA supplement for VANCOCIN (vancomycin HCl) Capsules (NDA No. 050606) – see here).

During the past 6-plus years, the CDER Exclusivity Board has issued scores of Letter Decisions (and there are more to come – see, e.g., page 26 here, as well as a recent Citizen Petition [FDA-2018-P-3284]).  Not all of the Board’s Letter Decisions are publicly available, and those that are public are not always easy to find as they can be buried in NDA Approval Packages.  But we’ve been able to rustle up some of them.

First up is the CDER Exclusivity Board’s October 2016 Letter Decision on eligibility for 5-year NCE exclusivity for E-Z-HD (barium sulfate) Powder for Oral Suspension, 98% (w/w). FDA approved E-Z-HD under NDA 208036 – a “literature-based” 505(b)(2) application – on January 11, 2016 for use in double contrast radiographic examinations of the esophagus, stomach and duodenum to visualize the gastrointestinal tract in patients 12 years and older.

NDA 208036 was (and continues to be) identified in FDA’s drug approval database as a “Type 7 – Drug Already Marketed without Approved NDA” application. FDA’s MAPP 5018.2, titled “NDA Classification Codes,” describes a “Type 7” NDA as follows:

A Type 7 NDA is for a drug product that contains an active moiety that has not been previously approved in an application, but has been marketed in the United States. This classification applies only to the first NDA approved for a drug product containing this (these) active moiety(ies).

Type 7 NDAs include, but are not limited to:

(1) The first post-1962 application for an active moiety marketed prior to 1938.

(2) The first application for an active moiety first marketed between 1938 and 1962 that is identical, related or similar (IRS) to a drug covered by a Drug Efficacy Study Implementation (DESI) notice.

(3) The first application for an IRS drug product first marketed after 1962.

(4) The first application for an active moiety that was first marketed without an NDA after 1962.

Whether the Type 7 (mis)classification or something else triggered a review by the CDER Exclusivity Board is unclear; however, the Board’s Letter Decision provides a nice reference tool for a point we’ve made in the past: An analysis of NCE exclusivity eligibility requires more than just consulting Drugs@FDA and the Orange Book, because those databases are incomplete. It requires, at the very least, a look-back at all NDAs approved by FDA under FDC Act § 505 since the FDC Act was signed into law by President Roosevelt on June 25, 1938, including those many, many NDAs whose approvals were withdrawn in the early 1970s under FDA’s NDA “clean-up initiative” (35 Fed. Reg. 11,929 (July 24, 1970)).

And that’s exactly what the CDER Exclusivity Board did in determining that E-Z-HD is not eligible for 5-year NCE exclusivity. According to FDA:

At least one drug product, Metabarin, containing barium sulfate as its active ingredient has been previously marketed under an NDA in the United States. On December 2, 1948, C.S.C. Pharmaceuticals, a division of Commercial Solvents Corporation, submitted an application (NDA 6624) for Metabarin under section 505(b) of the FD&C Act.  The application became effective on December 9, 1948.  As described in NDA 6624, Metabarin, an oral suspension, is a barium contrast medium used in the roentgenographic (X-ray) visualization of the esophagus, stomach, and intestinal tract.  The NDA indicates that Metabarin contains 99.656% barium sulfate (USP) along with a suspending agent, intended to provide a high degree of dispersibility, and two flavoring agents. . . .

The FD&C Act and FDA’s regulations preclude eligibility for 5-year NCE exclusivity when the drug contains an active moiety that has been previously approved in an application under section 505(b) of the FD&C Act. E-Z-HD contains barium sulfate, the sulfate salt of barium, as its active ingredient.  The active moiety in E-Z-HD is barium.21 Likewise, barium sulfate is the active ingredient and barium is the active moiety in Metabarin.  As noted above, the NDA for Metabarin became effective in 1948 and was deemed approved through the 1962 Amendments to the FD&C Act.  FDA’s regulations make clear that a drug product that is the subject of an application that was “deemed approved” under the 1962 Amendments is considered to be approved in an application under section 505(b) of the FD&C Act for purposes of determining whether certain products qualify for 5-year NCE exclusivity under section 505(c)(3)(E)(ii) and 505(j)(5)(F)(ii) of the FD&C Act.  Therefore, because the active moiety in E-Z-HD has been previously approved in an application under section 505(b) of the FD&C Act, i.e., the Metabarin NDA, E-Z-HD does not contain a new chemical entity and is not eligible for 5-year NCE exclusivity.

FDA is able to review drug approvals going back to 1938 because the Agency has a tool at its disposal that most folks do not have: the so-called “Ever-Approved List.” The Ever-Approved List a list of drug products purported to have been approved by FDA since 1938 under a marketing application submitted pursuant to FDC Act § 505.  Fortunately, we have a copy of the Ever-Approved List, which we understand the Agency will now supply through a FOIA request (though you might what to specify whether or not you would like the nearly 5,400-page PDF list or the Excel database. . . or perhaps both).  The list certainly comes in handy when speculating about the prospects of 5-year NCE exclusivity (see our previous post here).