Years after cancer flops, revamped Celldex shows promise in treating hives

Celldex Therapeutics regrouped in 2018 after a pair of major oncology flops, cutting both staff and pipeline to throw its resources behind two cancer-fighting antibodies. Now, as the company plots its comeback, it’s unveiling data for its leading program, a treatment not for cancer but for inflammatory skin conditions.

Celldex has some oncology assets in the works today and may be best known for the failure of its cancer vaccine Rintega and breast cancer treatment gelmatumumab vedotin. But the company has always been an antibody developer at heart, said Anthony Marucci, CEO and founder of Celldex.

“We refocused the company with some assets we had internally … [CDX-0159], it turned out, is a mast cell depleter and we thought that would be best in inflammatory diseases,” Marucci added. Mast cells are a type of immune cell that play a role in the onset and progression of inflammatory diseases.

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Celldex is developing the drug for various types of urticaria, also known as hives. The latest data, from a phase 1b study in patients with hives brought on by cold temperatures or by scratching the skin, show that a single dose of CDX-0159 stopped 18 of the 19 patients (95%) from developing hives when exposed to their triggers.

The results were presented Friday evening at the annual meeting of the European Academy of Allergy and Clinical Immunology. Celldex’s stock, which has sat under $3 for stretches in 2019 and 2020, jumped 50% to $48.58 in after-hours trading.

The drug’s effects lasted a median of 77 days in the 11 patients with cold urticaria and a median of 57 days in patients with symptomatic dermographism.

“The magnitude and durability of response from a single infusion is really encouraging,” Marucci said.

Patients like those Celldex recruited for the study don’t have many options besides antihistamines, and the study looked specifically at patients with cold urticaria that did not respond to antihistamines. Three of the study participants had received Genentech and Novartis’ Xolair in the past, but this drug is approved for chronic hives without a known cause and not specifically for cold urticaria or symptomatic dermographism.

RELATED: Novartis' Xolair follow-up banishes hives in 42% of patients with chronic hives

Moving forward, the company plans to start phase 2 studies in the first half of 2022 in spontaneous and inducible urticaria, that is, hives with no known cause and those with triggers, like cold temperatures. It also expects to report phase 1 data for CDX-0159 in patients with cholinergic urticaria—hives caused by sweating—and chronic spontaneous urticaria.

In the meantime, Celldex is preparing to test a version of CDX-0159 given by subcutaneous injection rather than intravenous infusion in healthy people and move the drug into more indications, said Margo Heath Chiozzi, M.D., Celldex’s head of regulatory affairs and program lead for CDX-0159. The first will be prurigo nodularis, which causes a rash so itchy it interferes with people’s sleep and everyday activities.

Beyond prurigo nodularis, there are several disease areas Celldex could go into next, including diseases of the eye, respiratory system, skin and gastrointestinal tract. All the while, the company will keep plugging away at its oncology programs, including a CD40-targeting antibody and a bispecific antibody targeting PD-L1 and CD27.

“We’ve started to understand where checkpoint therapies have been successful, but clearly, a lot of patients don’t respond,” said Tibor Keler, Ph.D., chief scientific officer of Celldex. “The programs we are developing in oncology aim to help improve the number of patients who can respond to immunotherapy.”