Improving clinical trial diversity remains an industry and regulatory linchpin in efforts to boost overall health equity — and by some accounts, progress has been frustratingly slow.
Recently, Congress thrust the issue to the forefront by mandating diversity in clinical trials within the 2022 omnibus spending bill. The FDA has since taken up the charge, publishing a draft guidance that would require industry sponsors to develop and submit a diversity plan, including enrollment goals for underrepresented racial and ethnic participants, before pivotal clinical trials for drugs. The law required the FDA to draft more guidance addressing how and when drugmakers must submit these plans by the end of 2023, but the agency hasn’t made it available yet, and some lawmakers are asking the FDA to produce it.
Meanwhile, major pharmas have devised their own strategies to tackle the issue. Japanese drugmaker Takeda Pharmaceuticals, for example, has set a lofty goal of achieving “unprecedented patient diversity” in phase 3 trials for a key psoriasis candidate, according to Karen Correa, vice president and head global clinical operations at Takeda.
The company’s TAK-279 is enrolling participants in a phase 3 trial with the ultimate goal of participants matching real-world data and the overall patient population. Takeda reported positive results from its phase 2b studies last year for TAK-279, an investigational oral allosteric tyrosine kinase 2 (TYK2) inhibitor, for treating plaque psoriasis and psoriatic arthritis.
Takeda acquired TAK-279 last year from Nimbus Therapeutics in a deal worth $4 billion, with high expectations the drug candidate would bulk up Takeda’s immunology portfolio. The candidate has been plugged to rival Bristol Myers Squibb’s psoriasis drug Sotyktu, which reached $170 million in global sales in 2023, according to the company’s end-of-year earnings report. As part of the deal, Takeda will make two additional and separate $1 billion payments to Nimbus after sales from the TAK-279 program reach $4 billion and $5 billion.
The phase 3 trial designs include a diversity action plan that Takeda based on the FDA’s initial guidance, according to Correa. In fact, the company has added diversity action plans to all new clinical trials since June 2022.
“I don't feel [there’s] pressure [from the FDA],” Correa said. “I think if anything, it's more about holding us accountable to do the right thing.”
Slow burn to overtake industry standards
In psoriasis, a lack of trial diversity can lead to critical gaps for physicians’ understanding of the disease and the way it presents. For example, psoriasis, which can cause scaly patches, can appear differently across skin tones.
“With patients of different color skin, you will see a difference in the disease,” Correa said. “For a lighter skinned patient, plaque psoriasis may present as red or pink; in a darker skinned person it may present as gray or violet; and in Hispanic patients it may appear as salmon colored or white-silver in appearance. If the research and prior studies are all white patients, and the data and the information and the imaging were all put in for white patients, imagine a physician or healthcare provider trying to diagnose a patient and leveraging the tools they have in front of them that might not represent the patients sitting in front of them.”
“We have to start somewhere. [If] more than 25% of sites have at least one patient of an underrepresented population, you're still moving in the right direction.”
Karen Correa
VP, head global clinical operations, Takeda
Beyond diagnosis, people of different races, ethnicities and sexes can also react differently to drugs and medical products, according to the FDA. But creating a trial that matches up to real-world patient populations requires an intentional approach, Correa said. Operational barriers and access to clinical trial sites can lead to underserved demographics and underrepresentation.
Takeda’s diversity strategy includes its PAVE approach — partnering with community stakeholders; addressing operational barriers that impede patient access; verifying that diversity and inclusion goals represent real-world data; and enhancing the diversity of investigative sites. In particular, partnering with community stakeholders has been effective, according to Correa.
“We have a really big awareness campaign where we're making sure we're collaborating and coordinating with other organizations within plaque psoriasis, [such as] pharmacies and different types of organizations and campaigns that help ensure people understand what is going on in complex psoriasis, and then making sure they have awareness of our trial,” Correa said.
Within their diversity action plans, Takeda is aiming to be above the industry standard when it comes to enrollment.
“We are tracking well above the industry benchmark, which is 25% or more of our clinical study sites are enrolling at least one patient from an underrepresented minority population,” Correa said.
However, the benchmark itself could be considered low.
“It's definitely a place of improvement, which is why we have the requirements going forward,” Correa said. “We have to start somewhere. [If] more than 25% of sites have at least one patient of an underrepresented population, you're still moving in the right direction.”
With a more diverse patient population represented in clinical trials for psoriasis, Takeda is aiming to improve outcomes down the line. The implications are broader than the company’s own phase 3 studies.
“Maybe what we'll see is more patients will be diagnosed earlier … they will be treated sooner and their quality of health will be better,” Correa said. “And that's the really important part to impact health disparities.”
