Update: On July 7, 2023, CellCentric announced that the FDA has approved orphan drug designation to inobrodib in addition to its previous fast-track approval that the drug recently received. 

“Orphan drug designation for inobrodib is an important milestone in our journey to develop an additional therapeutic option for patients with multiple myeloma,” Tomasz Knurowski, chief medical officer of CellCentric, stated in a press release. “We look forward to providing an update on our clinical data by the end of the year, which will help inform the next stage of development of inobrodib.”

Read more about its fast track approval from the FDA below: 

Over the past few years, we have been inundated with reports about the impact CAR-T and bi-specific products are making on the treatment protocols for multiple myeloma. Sometimes we may forget about development programs that have the potential to give us, myeloma patients, additional treatment options in the future. One such product is inobrodib, developed by the British company CellCentric.

Inobrodib is a “first in class” drug with a very different mechanism of action than what we have been learning about over the past some years. The drug inhibits the proteins p300 and CBP found on the surface of malignant cells, and this, in turn impacts the expression of several key cancer drivers. Inobrodib is a “small molecule” [compared to biologicals such as e.g., Darzalex].

This is of special interest to us patients, as the drug can be presented as a capsule that can be taken at home as opposed to having to travel to our local infusion center. CellCentric has already dosed about 200 patients with inobrodib as a monotherapy and in combination with familiar drugs such as pomalidomide and dexamethasone.  

The fast-track designation “is for relapsed refractory multiple myeloma after four or more prior lines of therapy, including a proteasome inhibitor, an immunomodulatory agent, and an anti-CD38 monoclonal antibody.”

Key conclusions reached so far are:

• “The safety profile is in line with preclinical data and inobrodib is well tolerated” at the dose selected from the dose escalation (safety and efficacy) studies.
• “All inobrodib-associated toxicities are manageable.”
• “The most common treatment related adverse effect, thrombocytopenia, was readily reversible.”
• “In contrast to other agents, inobrodib does not cause neutropenia or neuropathy.” 
• “Inobrodib monotherapy has encouraging signs of clinical activity against myeloma at the selected dose level.”

I will add a short note about the meaning/significance of “FDA fast track” designation. “Fast track is a process designed to facilitate the development and expedite the review of drugs to treat serious conditions and fill an unmet medical need. The purpose is to get important new drugs to the patient earlier." 

Even with fast-track regulatory review, we will need to wait a few more years before we can see inobrodib in clinical practice, and that is assuming that the human clinical trials meet all the endpoints desired by FDA. Still, it will be a worthwhile effort to follow further updates on the upcoming clinical outcomes.