In a turn of events that could reshape Novartis’ $2.9 billion acquisition of German biotech MorphoSys, the Swiss pharmaceutical giant has reported safety concerns that may delay the regulatory filing of MorphoSys’ leading drug candidate, pelabresib, by several years. This setback comes mere months after Novartis acquired MorphoSys, largely driven by positive phase 3 results for pelabresib, a potential treatment for myelofibrosis, a rare bone marrow cancer.
Initially, MorphoSys had aimed to submit approval applications for pelabresib in the U.S. and Europe by mid-2024. Early phase 3 trials indicated that the BET inhibitor could reduce spleen volume in myelofibrosis patients, though it fell short on symptom improvement—a key measure in assessing the drug’s efficacy. By mid-2024, Novartis CEO Vas Narasimhan indicated that the company was awaiting 48-week data to solidify filing plans. Now, with updated data in hand, Novartis has decided to delay the approval process further.
The decision follows the emergence of a safety signal—an imbalance in the rate of malignant transformations, which involve myelofibrosis progressing into acute myeloid leukemia, a highly aggressive form of cancer. Novartis is working closely with health authorities to assess whether additional studies are necessary to establish a more favorable risk-benefit profile for pelabresib.
“We intend to monitor these patients for a longer period and carefully review the data over the next year,” Narasimhan shared in a recent media call. “Additional studies may be needed to address both the safety concerns and to strengthen the overall data package. This delay could push our filing plans out by a couple of years.”
The delays have led Novartis to reconsider MorphoSys’ valuation, resulting in an $800 million impairment on the acquisition, which was reported in Novartis’ latest third-quarter results. This financial adjustment was recorded just before Novartis completed its buyout of minority MorphoSys shareholders.
Alongside pelabresib, Novartis has made other pipeline updates. The company announced the discontinuation of XXB750, a candidate for blood pressure and heart failure, citing early data assessments. Additionally, Novartis halted development of ligelizumab for food allergies and ceased work on ianalumab in autoimmune hepatitis after unfavorable phase 2 results. However, trials for ianalumab continue in other areas, such as Sjögren’s syndrome and lupus.
The decision to delay pelabresib’s filing underscores Novartis’ cautious approach to safety and highlights the challenges pharmaceutical companies face in managing risks and advancing complex drug development programs.
