Acella, facing 43 'serious' side effect reports, pulls dozens of lots of sub-potent thyroid drug

FDA
Acella pulled two lots of its hypothyroidism drug NP Thyroid in September over similar sub-potency concerns. (Andrew Harnik, Associated Press)

Last May, Acella Pharmaceuticals pulled 13 lots of its prescription hypothyroidism med NP Thyroid in the U.S. after testing revealed an excess of one of the drug's main ingredients. Now, the company is facing the opposite problem.

Acella is recalling certain lots of five separate doses of NP Thyroid after routine testing showed the batches weren't potent enough. Specifically, the product in the suspect lots contains less than 90% of the labeled amount of liothyronine and (or) levothyroxine, the drug's active pharmaceutical ingredients (APIs), the company said in a notice posted on the FDA's website. Dozens of cases of "serious" side effects could be related to the potency issue.

Back in September, Acella pulled one lot each of its 15-mg and 120-mg thyroid tablets for the same reason, noting the med may have contained as little as 87% of the listed amount of levothyroxine. It dealt with the reverse predicament last May, when it had to pull 13 lots of NP Thyroid after testing uncovered an excess of the med's other active ingredient, liothyronine.

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This time, Acella is pulling significantly more of its product from U.S. shelves. The latest recall covers 35 commercial lots of various dosages in 100-count bottles, plus three sample lots containing seven-count bottles. 

As of April 29, Acella said it had received 43 reports of "serious" side effects possibly linked to the recall. Hypothyroidism patients who take a lower-strength dose than intended could suffer symptoms of their disease, which run the gamut from fatigue and constipation to hair loss, slow heart rate and swelling of the thyroid gland. For pregnant women and newborns with an underactive thyroid, there are other, greater risks at play, Acella warned.

The company flagged a "reasonable risk of serious injury" in those patients, which could include early miscarriage, fetal hyperthyroidism—where the thyroid gland produces too much of the hormone thyroxine—and impaired neural and skeletal growth in the womb. Meanwhile, older patients and those with underlying heart disease could experience "toxic cardiac manifestations" of hyperthyroidism such as heart pain, palpitations or irregular heart beat, Acella said. 

The company is working to recover the recalled product. Acella recommends patients in possession of the suspect meds seek advice from a healthcare professional rather than halting treatment outright. 

The bottles carried expiration dates ranging from April 2021 to March 2022. The company shipped the affected doses between March 2020 and March 2021. 

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As the pharma supply chain becomes increasingly international, drugmakers have frequently turned to contract manufacturers for help—but those partners can sometimes throw quality risks into the equation. Acella has learned that lesson the hard way. 

The FDA last year slapped Acella with a warning letter that cited the company for failing to use the appropriate assays for the active ingredients in NP Thyroid, which were made by a manufacturing partner. The warning followed a regulator investigation that ran from December 2019 through January 2020. 

Acella managed to fix the issues, though not in time to prevent its NP Thyroid recall last May, which was tied to super-potent testing results. An FDA follow-up investigation of Acella's CMO facility that same month found that the 13 lots in question exceeded the drug's specified strength.

At the time, the regulator warned that NP Thyroid's "narrow therapeutic range" meant out-of-spec dosing could lead to serious safety concerns. 

Acella isn't the only company whose levothyroxine- and liothyronine-based thyroid product has entered the FDA's crosshairs. Westminster Pharmaceuticals in 2018 pulled all lots of its generic thyroid med using the ingredients because it was made with API from China's Sichuan Friendly Pharmaceutical. 

In March 2018, the FDA slapped a ban on all of Sichuan's products after an inspection turned up big problems at the Chinese company's manufacturing plant. 

Meanwhile, the FDA hit Phoenix-based RLC Labs with a warning letter last year after the company failed to fix quality control issues behind the September recall of 483 lots of thyroid meds. The FDA flagged six samples of the company's WP Thyroid and Nature-Throid products for subpar potency, out of a total 10 sampled lots.