The FDA sent a letter to James D. Weir, president and chief executive officer of Primus in Scottsdale, AZ. The letter demanded that Primus cease distribution and immediately recall specific Limbrel lots, which include:
• Limbrel (flavocoxid) 250 mg capsules
• Limbrel250 (250 mg flavocoxid with 50 mg citrated zinc bisglycinate) capsules
• Limbrel (flavocoxid) 500 mg capsules
• Limbrel500 (500 mg flavocoxid with 50 mg citrated zinc bisglycinate) capsules
FDA Letter to Primus
The agency wrote in its letter to Mr. Weir at Primus: “The FDA has determined that these Limbrel products are unapproved new drugs and represent a serious health hazard. Between January 1, 2007, and November 9, 2017, FDA received 194 adverse event reports associated with the use of Limbrel products.”
Primus Liver Injury & Hypersentsitivity Pneumonitis (HP)
The FDA letter further stated that adverse event reports it had received “identified a close relationship between the use of Limbrel and adverse events involving the development of drug-induced liver injury (DILI), pancreatitis, and hypersensitivity pneumonitis (HP).” Those health problems can present varying degrees of severity, ranging from mild to life-threatening.
FDA: Limbrel Products Unapproved
The FDA further wrote: “In addition, your Limbrel products are unapproved new drugs distributed in violation of sections 301(d) and 505(a) of the Federal Food, Drug, and Cosmetic Act (FD&C Act) [21 U.S.C. § 331(d) and 355(a)].” The agency letter added that the claims on the product labeling establish that the Limbrel products are drugs because they are intended for use in the cure, mitigation, treatment, or prevention of disease. FDA said the label claims establish that the product is a drug because of such language as “clinical dietary management of the metabolic processes of osteoarthritis.”
On its Limbrel website, Primus pushed back at the FDA, appearing to blame the agency for the withdrawal. Primus said the action to withdraw the Limbrel products from the market was “in response to repeated aggressive press releases from the FDA” and the letter it received from the FDA on December 19.
Unwarranted Pressure from FDA?
The Primus statement on its web site read in part: “Primus Pharmaceuticals, in response to unwarranted pressure from the FDA, has voluntarily suspended promotion and sale of Limbrel, an important and in many cases the only medical option for people suffering from osteoarthritis, pending Primus receiving requested safety data held by the FDA and meeting with the FDA as requested.”
Limbrel: Medical Food or Drug?
The company further questioned the FDA’s determination that Primus had marketed Limbrel as a drug, rather than a food. Through its Washington law firm, Primus’ formal response to FDA included this statement: “For nearly 14 years, Limbrel has been marketed as a medical food dispensed by prescription and under physician supervision, with over 2 million packages sold and sampled in that time to an estimated 450,000 patients.”
In their response dated Dec. 20, Primus’ lawyers claimed Limbrel does meet the statutory definition of a medical food as set forth in the Orphan Drug Act. “In fact, Limbrel has been referenced as such in many peer-reviewed nutritional, regulatory, clinical, and scientific peer-reviewed articles.”
Primus’ response also countered FDA’s adverse-event claim. Primus said that historically, “both FDA and Primus have received very low numbers of reports of acute hypersensitivity pneumonitis (AHP) and elevated liver function tests (LFTs).” The company added that the reactions have been temporary and medically reversible.
Primus has reportedly requested further meetings with FDA to lobby that Limbrel is safe and should be considered a medical food. If that effort fails, Primus indicated it might pursue a reclassification of the product as a nutritional supplement, according to a Jan. 2018 report in The Arizona Republic.
The newspaper quoted Mr. Weir as saying, “We don’t understand why this product has been on the market for so long with such consistent feedback and use, and now is an issue.”
FDA Recommends ceasing Limbrel Use
In its Nov. 2017 warning, the FDA also advised health care providers who are aware that their patients are taking Limbrel to tell them to stop using it.
Limbrel Injury Symptoms
Of the 194 adverse event reports regarding Limbrel that the FDA received, 30 gave sufficient information for FDA medical experts to determine that Limbrel was likely associated with these adverse events. The agency has recently seen a spike in the number of serious, potentially life- threatening health problems associated with Limbrel, including drug-induced liver injury and hypersensitivity pneumonitis.
Various symptoms of drug-induced liver injury may include jaundice, nausea, fatigue, and gastrointestinal discomfort. Anyone experiencing any of these symptoms is advised to contact a health care provider right away. Symptoms of hypersensitivity pneumonitis may include fever, chills, headache, cough, chronic bronchitis, shortness of breath or trouble breathing, weight loss, fatigue. Anyone experiencing any of these symptoms, is also advised to contact a health care provider right away.