IPH4102, Innate Pharma’s investigational antibody, reduced tumor volume in 36% of patients with cutaneous T-cell lymphoma (CTCL) in a Phase 1 trial. Patients were heavily pre-treated, having received at least two prior lines of therapy.
Responses were particularly better among those without large cell transformation — a marker of poor prognosis in CTCL — with 51.7% of patients seeing a reduction in disease burden.
“This patient population remains a high unmet medical need as they continue to progress through several lines of treatments,” Martine Bagot, principal investigator of the study and head of the dermatology department at the Saint-Louis Hospital in Paris, said in a press release. “Together with a favorable safety profile, IPH4102 could emerge as a key therapeutic option in aggressive T-cell lymphomas.”
Results were recently presented at the EORTC Cutaneous Lymphoma Group meeting in St. Gallen, Switzerland, in a presentation titled “IPH4102 in relapsed/refractory cutaneous T cell lymphoma (CTCL): Results of the first-in-human multicenter phase 1 study.”
IPH4102 is an antibody that targets KIR3DL2, a protein receptor found in 65% of all CTCL patients and in up to 85% of those with aggressive CTCL subtypes, such as Sézary syndrome and transformed mycosis fungoides (tMF).
The treatment candidate has already received orphan drug status in both the United States and the European Union for the treatment of CTCL.
The ongoing Phase 1 trial (NCT02593045) is being conducted in five centers in France, the Netherlands, United Kingdom, and the United States. It has enrolled 44 patients with advanced CTCL who had received at least two prior lines of treatment.
The study was conducted in two parts. First, researchers aimed to study the treatment’s safety and determine the best dose for further use, called the recommended Phase 2 dose. This part included 25 CTCL patients whose tumor cells produced the KIR3DL2, who received one of 10 doses of IPH4102.
In the second part, researchers included 15 patients with Sézary Syndrome and four with tMF, who received the recommended Phase 2 dose.
As of June 28, 2018, nine patients were still receiving the treatment and patients had been followed for a median of 12.7 months. Overall, 36.4% of patients responded to IPH4102, including two patients (4.5%) whose disease was gone after treatment. Also, 54.5% of patients achieved disease stabilization, accounting for a clinical benefit rate of 90.9%.
Responses lasted a median of 13.8 months, and patients remained alive and without any signs of disease progression for a median of 8.2 months.
The best responses, however, were seen in a group of patients without evidence of large cell transformation. These patients achieved an overall response rate of 51.7% and lived for a median of 12.8 months without seeing their disease progress.
Patients also reported improvements in their quality of life, including a reduction in itching.
IPH4102 was generally safe and well-tolerated. The most common adverse events reported were fluid accumulation in the legs and arms (peripheral edema), lack of energy, fatigue, cough, fever, diarrhea, and joint pain. The reactions were mostly mild.
“IPH4102’s encouraging clinical activity provides substantial support to explore its potential therapeutic benefits not only in [Sézary syndrome] patients but also in other T-cell lymphoma patient populations,” Bagot said.
Pierre Dodion, chief medical officer of Innate Pharma, said: “We look forward to providing more insight into the data and subsequent clinical development plans in the near future,”
Innate Pharma expects the findings to support a broader Phase 2 clinical program for IPH4102, which should include patients with Sézary syndrome and other subtypes of T-cell lymphomas.