FDA Rejects Takeda's Application to Relaunch Natpara Parathyroid Hormone Therapy

Compiled by Fan Dongdong

Recently, the U.S. FDA rejected Takeda's parathyroid hormone Natpara from returning to the market. The newly released Complete Response Letter (CRL) has also completely shattered the company’s vision of re-launching this parathyroid hormone injection for sale.

Natpara, developed by Takeda, is a treatment drug that helps patients manage low blood calcium caused by hypoparathyroidism. It is also the first prescription parathyroid hormone to be approved by the U.S. FDA. However, in September 2019, due to the potential for rubber particles from the rubber septum of the Natpara cartridge, Takeda ultimately had to announce the recall of all batches of Natpara injection products in the U.S. market over safety concerns.

During the 14-day treatment with Natpara, patients need to inject the medication daily by puncturing the rubber septum of the cartridge. Repeated puncturing may directly cause rubber fragments to detach from the cartridge. At that time, Takeda claimed that the detached rubber stopper could potentially clog the needle, resulting in an insufficient drug dosage being injected into the patient’s body. The recall was classified as a Class I event.

In August 2021, in order to address the impact of the recall and expedite the re-launch of Natpara, Takeda submitted a Prior Approval Supplement (PAS) for Natpara to the U.S. regulatory authority, aiming to resolve the rubber particle issue. The company proposed modifications to the Natpara device components, including the adoption of a new septum and a new needle.

However, despite efforts to address the safety concerns of Natpara, the U.S. FDA stated in its recent complete response letter (CRL) to Takeda that the Prior Approval Supplement (PAS) cannot be approved under the current circumstances. Takeda has expressed that the company will evaluate the specific details of the CRL to determine the next steps.

Natpara was first approved by the FDA in September 2015. The drug needs to be used with calcium and vitamin D to control abnormally low calcium levels in patients with hypoparathyroidism. Natpara can help the intestines absorb more calcium by activating vitamin D, while increasing the amount of calcium reabsorbed by the kidneys, and also promoting the release of necessary calcium from bones.

Currently, although Natpara therapy is unlikely to return to the commercial market in the short term, Takeda intends to continue providing the drug free of charge to patients already enrolled in the Natpara Special Use Program. The U.S. FDA has also provided the necessary regulatory oversight and discretion for this purpose. The Natpara Special Use Program was implemented after the drug's recall in September 2019, aiming to help patients who were previously treated with Natpara continue using it and avoid potentially life-threatening complications from abrupt discontinuation.

Reference Source: Return of Takeda’s Parathyroid Hormone Injection Delayed Indefinitely