The FDA has declined to approve an injectable version of Johnson & Johnson's drug Rybrevant for a type of lung cancer, the drugmaker said.

The FDA's so-called complete response letter was related to observations as part of a standard pre-approval inspection at a manufacturing facility, J&J said.

It is unrelated to the product formulation, or the efficacy and safety data submitted, the company said, adding that the FDA has not requested any additional clinical studies.

The company was seeking approval for the subcutaneous version of the drug to treat patients with non-small cell lung cancer (NSCLC) who have mutated form of a gene called epidermal growth factor receptor (EGFR), which causes rapid tumor cell growth.

J&J said it is working closely with the FDA to resolve the issues and bring the subcutaneous version to patients as quickly as possible.

In August, the drug in combination with J&J's existing drug, lazertinib, was approved as a first-line treatment for NSCLC patients with the mutated form of the EGFR gene.

Rybrevant disrupts growth of EGFR and another gene called MET to slow down or stop the spread of tumorous cells, and lazertinib inhibits their rapid reproduction.

J&J's Rybrevant is also approved for the treatment of NSCLC as a monotherapy in patients whose disease has progressed after chemotherapy, and in combination with chemotherapy for patients with the EGFR mutation in the U.S.

The currently approved intravenous formulation of Rybrevant was not impacted, the company added.