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Notice2026-19912

FHTA LLC; Withdrawal of Approval of New Drug Application for MYSOLINE (Primidone) Suspension, 250 Milligrams/5 Milliliters

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Published
September 29, 2026

Issuing agencies

Health and Human Services DepartmentFood and Drug Administration

Abstract

The Food and Drug Administration (FDA or Agency) is withdrawing approval of new drug application (NDA) 010401 for MYSOLINE (primidone) suspension, 250 milligrams (mg)/5 milliliters (mL), held by FHTA LLC (FHTA). FHTA agreed to withdrawal of approval of this application and has waived its opportunity for a hearing.

Full Text

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<title>Federal Register, Volume 91 Issue 187 (Tuesday, September 29, 2026)</title>
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[Federal Register Volume 91, Number 187 (Tuesday, September 29, 2026)]
[Notices]
[Page 61408]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-19912]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration

[Docket No. FDA-2026-N-10505]


FHTA LLC; Withdrawal of Approval of New Drug Application for 
MYSOLINE (Primidone) Suspension, 250 Milligrams/5 Milliliters

AGENCY: Food and Drug Administration, HHS.

ACTION: Notice.

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SUMMARY: The Food and Drug Administration (FDA or Agency) is 
withdrawing approval of new drug application (NDA) 010401 for MYSOLINE 
(primidone) suspension, 250 milligrams (mg)/5 milliliters (mL), held by 
FHTA LLC (FHTA). FHTA agreed to withdrawal of approval of this 
application and has waived its opportunity for a hearing.

DATES: Approval is withdrawn as of September 29, 2026.

FOR FURTHER INFORMATION CONTACT: Aaron Young, Center for Drug 
Evaluation and Research, Food and Drug Administration, 10903 New 
Hampshire Ave., Bldg. 51, Rm. 6220, Silver Spring, MD 20993-0002, 301-
796-8083, <a href="/cdn-cgi/l/email-protection#1c7d7d6e737232657369727b5c7a787d3274746f327b736a"><span class="__cf_email__" data-cfemail="f49595869b9ada8d9b819a93b4929095da9c9c87da939b82">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION: FDA initially approved NDA 010401 for 
MYSOLINE (primidone) suspension, 250 mg/5 mL, on July 5, 1956. In 2001, 
MYSOLINE (primidone) suspension, 250 mg/5 mL, was discontinued after 
antimicrobial effectiveness testing raised concerns about potential 
microbial contamination, in particular with Pseudomonas aeruginosa. In 
the Federal Register of January 2, 2026 (91 FR 148), FDA determined 
that MYSOLINE (primidone) suspension, 250 mg/5 mL, was withdrawn from 
sale for reasons of safety or effectiveness. FDA noted that, as a 
scientific matter, before MYSOLINE (primidone) suspension, 250 mg/5 mL, 
could be considered for reintroduction to the market, a reformulation 
would be required including establishment of preservative content 
acceptance criteria and correlation with passing antimicrobial 
effectiveness testing results. FDA stated that the NDA holder for 
MYSOLINE (primidone) suspension, 250 mg/5 mL, would have to demonstrate 
the safety and effectiveness of the reformulated product. FDA further 
stated that, at that time, no new formulation had been approved for 
MYSOLINE (primidone) suspension, 250 mg/5 mL.
    On June 12, 2026, FDA asked FHTA whether it intended to reformulate 
MYSOLINE (primidone) suspension, 250 mg/5 mL, to establish preservative 
content acceptance criteria and correlation with passing antimicrobial 
effectiveness testing results, or whether FHTA would agree to waive the 
opportunity for hearing and permit FDA to withdraw approval of NDA 
010401 under 21 CFR 314.150(d) (Sec.  314.150(d)). FDA referred to its 
determination that MYSOLINE (primidone) suspension, 250 mg/5 mL, was 
withdrawn from sale for reasons of safety or effectiveness in 
connection with concerns regarding potential microbial contamination, 
in particular with Pseudomonas aeruginosa. On June 22, 2026, FHTA 
responded that it was not seeking a hearing and agreed to withdrawal of 
NDA 010401 pursuant to Sec.  314.150(d).
    For the reasons discussed above, which FHTA does not dispute in its 
response, and in accordance with FHTA's response, approval of NDA 
010401 for MYSOLINE (primidone) suspension, 250 mg/5 mL, and all 
amendments and supplements thereto, is withdrawn under Sec.  
314.150(d). Distribution of MYSOLINE (primidone) suspension, 250 mg/5 
mL, into interstate commerce without an approved application is illegal 
and subject to regulatory action (see sections 505(a) and 301(d) of the 
Federal Food, Drug, and Cosmetic Act (21 U.S.C. 355(a) and 331(d)).

Grace R. Graham,
Deputy Commissioner for Policy, Legislation, and International Affairs.
[FR Doc. 2026-19912 Filed 9-28-26; 8:45 am]
BILLING CODE 4164-01-P


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Indexed from Federal Register on September 29, 2026.

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