FDA Issues Another CRL for Amorphous Dasatinib Receives in CML and ALL

The FDA has issued a new complete response letter (CRL) to Xspray Pharma for Dasynoc, an amorphous formulation of dasatinib, for the treatment of patients with chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL), according to a news release from the company.¹

The CRL relates to previously communicated Good Manufacturing Practice (GMP) issues observed at the third-party manufacturer NerPharMa, as well as a request for additional commercial-scale consecutive batch data following corrective actions that have already been implemented. Notably, the FDA did not raise questions regarding the clinical data, bioequivalence, or stability of the agent.

Why did amorphous dasatinib receive a complete response letter?

The CRL is tied to outstanding GMP observations at NerPharMa and the agency’s request for additional commercial-scale consecutive batch data. According to Xspray Pharma, the FDA did not raise questions about Dasynoc’s clinical data, bioequivalence, or stability. Additionally, the risk of medication error raised in previous CRLs has been resolved. NerPharMa has completed its remediation work at the facility and notified the FDA, though the agency has yet to determine whether a reinspection is required to finalize its assessment.

“The CRL confirms that the remaining uncertainty is now linked to NerPharMa sufficiently addressing the FDA’s observations at their manufacturing site and batch data from consecutive manufacturing runs being provided,” said Blake Leitch, chief executive officer of Xspray Pharma, in the press release.¹ “As expected, this will require a new drug application [NDA] resubmission.”

What are the next steps for amorphous dasatinib?

Because Xspray’s launch planning already required additional commercial-scale batches, the company said it will prioritize manufacturing these batches to satisfy the FDA’s request for additional data. Xspray intends to resubmit the application as soon as possible within 2026 to secure a new Prescription Drug User Fee Act (PDUFA) date and subsequently accelerate the launch.

Developers noted that they will continue preparing for commercial launch in the US so that Dasynoc can reach oncologists and patients with CML and ALL once all regulatory conditions have been fulfilled. They also stated that the CRL does not change their financial position as communicated in its recent second-quarter report.

What is amorphous dasatinib?

Dasynoc is a product candidate based on dasatinib, an established treatment for CML and ALL, among other indications. The amorphous formulation of dasatinib leverages patented HyNap technology and has demonstrated bioequivalence at a 30% lower dose than reference dasatinib (Sprycel). Developers engineered the agent to enable concomitant use with acid-reducing medicines such as proton pump inhibitors, which are commonly co-prescribed for patients with CML and ALL and may affect the absorption of conventional dasatinib.

What is amorphous dasatinib’s regulatory history?

The path to approval for amorphous dasatinib has been extensive, with the FDA’s concerns consistently relating to manufacturing rather than clinical data. Of note, after resubmission of the NDA in May 2025 with a PDUFA date of October 7, 2025, the FDA issued a different CRL in October 2025 based on GMP observations at a contract manufacturer, pausing approvals from that facility pending corrective actions.²

“If approved, Dasynoc would provide a more adaptable dasatinib option—particularly beneficial for patients requiring acid suppression or reduced dosing due to comorbidities. Rather than replacing current tyrosine kinase inhibitors [TKIs] like imatinib [Gleevec], nilotinib [Tasigna], or bosutinib [Bosulif], it would complement them by addressing real-world pharmacologic and tolerability gaps,” Yan Leyfman, MD, co-founder and executive director of MedNews Week, stated in a previous written correspondence to CancerNetwork regarding the drug.

References

1. Xspray Pharma receives complete response letter (CRL) from FDA for Dasynoc. News release. Xspray Pharma AB. August 19, 2026. Accessed August 20, 2026. https://tinyurl.com/34kjkrjm
2. Xspray Pharma provides update on the FDA process for Dasynoc—observations at contract manufacturer delay approval. News release. Xspray Pharma AB. October 8, 2025. Accessed August 20, 2026. https://tinyurl.com/yc366ske