Complex causes behind bottleneck
The cause of the current bottleneck for myeloma patients is complex. It stems from a shortage of raw materials and supply chain restraints, among other things.
While the biggest impact of shortages has been on patients with multiple myeloma, Dr. Patel pointed out that these constraints are also affecting patients with lymphoma at her institution, but to a lesser degree.
“This is multifactorial as to why, but most of the issues arise from manufacturing,” Dr. Patel said in an interview. “Initially, the FDA limited how many slots each new product could have per month, then there was a viral vector shortage, and then the quality-control process the FDA requires takes longer than the manufacturing of the cells actually do.”
On top of that, “we have about a 5% manufacturing fail rate so far,” she added. Such failures occur when the cells taken from a patient cannot be converted into CAR T cells for therapy.
Matthew J. Frigault, MD, from the Center for Cellular Therapies, Mass General Cancer Center, Boston, explained that the growing excitement about the potential for cellular therapy and recent approvals for these products for use in earlier lines of treatment have increased demand for them.
There are also problems regarding supply. Manufacture and delivery of CAR T is complicated and takes time to scale up, Dr. Frigault pointed out. “Therefore, we are seeing limited access, more so for the BCMA-directed therapies [which are used for myeloma].”
The shortages and delays likely involve two main factors. “For the newer indications, there is a significant backlog of patients who have been waiting for these therapies and have not been able to access them in the clinical trial setting, and manufacturing is extremely complicated and not easily scaled up,” he said.
“That being said, manufacturers are trying to increase the number of available manufacturing slots and decrease the time needed to manufacture cells,” Dr. Frigault commented.
Delays in access to myeloma CAR T-cell therapy are also affecting patient care at Fox Chase Cancer Center in Philadelphia. “We have had about one slot every 2 months for Abecma,” noted Henry Fung, MD, chair of the department of bone marrow transplant and cellular therapies at Fox Chase. “For Carvykti, there are only 32 certified centers in [the] U.S., and access is very limited.”
Dr. Fung explained that they have had to offer alternative treatments to many of their patients. “There are rumors that there’s shortage in obtaining raw materials, such as the virus used for transduction, although we have not encountered any problems in other CAR T products used for lymphomas.”
Pharma companies trying to meet the demand
This news organization reached out to the manufacturers of CAR T products. All have reported that they are doing what they feasibly can to ramp up production.
“The complexity of delivering CAR T-cell therapies is unlike any other traditional biologic or small-molecule medicine, using a patient’s own cells to start a highly sophisticated and personalized manufacturing process,” commented a spokesperson for BMS, which has two CAR T-cell products currently on the market.
“In this nascent field of cell therapy, we continue to evolve every day, addressing supply and manufacturing challenges head on by applying key learnings across our three state-of-the-art cell therapy facilities and two new facilities in progress.
“We have been encouraged by a steady increase in our manufacturing capacity, and we continue efforts to ramp up further to meet the demand for our cell therapies,” the BMS spokesperson commented. “We have already seen improvements in the stabilization of vector supply and expect additional improvements in capacity in the second half of 2022.”
Novartis said much the same thing. They have a “comprehensive, integrated global CAR-T manufacturing footprint that strengthens the flexibility, resilience, and sustainability of the Novartis manufacturing and supply chain. Together with an improved manufacturing process, we are confident in our ability to meet patient demand with timely delivery,” according to a Novartis spokesperson.
The spokesperson also pointed out that the company has continuously incorporated process improvements that have significantly increased manufacturing capacity and success rates for patients in need of CAR T cells.
“Data presented at [the] American Society of Hematology annual meeting in 2021 showed the Novartis Morris Plains facility, our flagship CAR T manufacturing site, had commercial manufacturing and shipping success rates of 96% and 99%, respectively, between January and August 2021,” according to the spokesperson.
Legend and Janssen, the companies behind Carvykti, one of the two approved cell products for myeloma, which launched earlier in 2022, said that they have continued to activate certified treatment centers in a phased approach that will enable them to expand availability throughout 2022 and beyond.
“This phased approach was designed to ensure the highest level of predictability and reliability for the patient and the certified treatment centers,” the spokesperson said. “We understand the urgency for patients in need of Carvyki and are committed to doing everything we can to accelerate our ability to deliver this important cell therapy in a reliable and timely manner.”
With regard to the industry-wide supply shortage of lentivirus, Legend and Janssen say they have put in place multiple processes to address the shortage, “including enhancing our own internal manufacturing capabilities of this essential drug substance, to ensure sufficient and sustained supply.”