FDA issues CRL for AstraZeneca’s subcutaneous Saphnelo application

The U.S. Food and Drug Administration has issued a complete response letter for AstraZeneca’s Biologics License Application seeking approval of a subcutaneous, self‑administered formulation of Saphnelo (anifrolumab) for adults with systemic lupus erythematosus, AstraZeneca announced Feb. 3. The company says it has provided requested information, but the public announcement did not include details of the agency’s deficiencies or a timeline for next steps.

Saphnelo is already marketed in an intravenous formulation that the FDA approved following a BLA submission dated July 22, 2020 and received July 31, 2020 under BLA 761123. The approval letter for the intravenous product lists the drug as indicated “for the treatment of adult patients with moderate to severe systemic lupus erythematosus (SLE), receiving standard therapy,” and authorizes a 300 mg/2 mL (150 mg/mL) vial. The approval-letter excerpt also identifies manufacturing sites for the approved intravenous product, including AstraZeneca’s Frederick Manufacturing Center in Maryland and facilities in Nijmegen, Netherlands and Sodertalje, Sweden.

The public materials supplied by AstraZeneca and FDA records do not tie a BLA number to the subcutaneous application, nor do they state whether the subcutaneous filing is a separate BLA or a supplement to the intravenous approval. That distinction matters for regulators and for patients because supplemental filings and new BLAs can involve different data requirements on clinical efficacy, safety, or manufacturing controls.

Records from FDA review units show a prior exchange of labeling and packaging material for the intravenous product in 2021. A label and labeling review by the Office of Prescription Drug Promotion and related reviewers cites submissions of revised container and carton labeling on April 20, 2021 and May 19, 2021, and references an information-request response from AstraZeneca on May 12, 2021. In an OPDP memorandum dated July 14, 2021, reviewers concluded: “Thus, we find the submitted Prescribing Information, trade container labels and carton labeling acceptable from a medication error perspective. We have no additional recommendations at this time.” The memo includes RCM No. 2020-1632 and multiple internal reference IDs with staff signoffs dated July 20, 2021.

AstraZeneca has precedent for receiving CRLs. In an archived October 2015 press release about a different product, the company described a CRL that stated “more clinical data are required to support the application. This includes clinical trial data from ongoing or completed studies and may require information from new studies,” and said it would “work closely with the FDA to determine the appropriate next steps.”

Absent the text of the current CRL, it is unclear whether the FDA’s action relates to additional clinical trials, manufacturing changes, device or auto‑injector performance, labeling, or chemistry, manufacturing and controls. The company’s brief statement that it provided requested information leaves open whether AstraZeneca believes the CRL’s issues are resolved or whether the submission will require further amendment or additional studies.

For patients and clinicians, a subcutaneous, self‑administered formulation could be a meaningful convenience and access improvement compared with an infusion. For investors and regulators, the next public steps will be whether the FDA supplies a redacted CRL or summary and whether AstraZeneca files an amendment, requests a meeting with the agency, or provides additional data to address the regulator’s concerns.