Injecting ilixadencel into the tumors of newly diagnosed metastatic kidney cancer patients provoked a potent immune response to the disease, according to the first stage of a Phase 1/2 clinical trial.
In addition, the median length of time that patients have survived after treatment with ilixadencel —42 1/2 months — has passed the historical overall median survival rate of those treated with standard therapies. And the ilixadencel-related duration may increase because researchers are still following patients.
Ilixadencel is a cancer vaccine that Immunicum developed around immune system components known as dendritic cells. The Phase 1 portion of the trial (NCT01525017) covered patients with newly diagnosed metastatic renal cell carcinoma, or mRCC. That is a cancer that has spread from the kidneys to other parts of the body.
Researchers reported the results in the Journal for ImmunoTherapy of Cancer. The study is titled “Intratumorally injected pro-inflammatory allogeneic dendritic cells as immune enhancers: A first-in-human study in unfavourable risk patients with metastatic renal cell carcinoma.”
The trial covered 12 newly diagnosed mRCC patients whom doctors considered medium or poor survival risks. Researchers assessed ilixadencel’s safety and effectiveness.
Patients received two injections of ilixadencel over 15 days, directly into their tumor. Then surgeons removed part or all of their kidneys, and patients received standard-of-care therapy.
Researchers discovered a massive infiltration of immune-system components known as CD8+ T-cells in five of the 12 kidney tumors that surgeons removed. The research team also saw evidence of a solid anti-tumor immune response in patients’ blood: It contained higher levels of immune cells that produce anti-tumor proteins.
Five patients were still alive by May 2017, meaning that their median overall survival rate had reached 48 months.
Ilixadencel proved safe, with no severe adverse effects.
The article in the Journal for ImmunoTherapy for Cancer “represents the complete analysis of data from the Phase 1/2 trial, and we are pleased to have achieved peer-reviewed publication in a well-reputed international journal,” Alex Karlsson-Parra, chief scientific officer of Immunicum, said in a press release.
Although the study was completed in 2014, “we are still following the patients,” he said. As of May 2017, five out of the 11 patients who could be evaluated were still alive, he noted. Their mean overall survival rate compared favorably with the historical rate achieved by standard-of-care therapies, he added.
“One of the five patients still alive experienced a complete regression of all brain and liver metastases” — kidney cancer that had spread to those regions, he said. “The patient has also demonstrated a nearly total regression of lung metastases and was metastasis-free following surgical removal of a small remaining lung metastasis at the end of 2016. Although this is only one case study, it is a promising initial result considering the expected poor prognosis for these patients.”
The favorable results support the randomized, multi-center Phase 2 part of the Phase 1/2 trial, Immunicum said. The new round of the MERECA study (NCT02432846) will evaluate the effectiveness of a combination of ilixadencel and Sutent (sunitinib) as a kidney cancer treatment. Researchers are in the midst of recruiting patients for the trial.
The U.S. Federal Drug Administration has already approved Sutent as a kidney-cancer therapy.
“Apart from the good safety profile, the data provided early indications that ilixadencel given in conjunction with sunitinib could have a potential synergistic antitumor effect, which we will be further investigating in the ongoing MERECA trial,” Karlsson-Parra said. “We believe that the future of cancer treatment lies in the rapidly evolving landscape of combination therapies, and ilixadencel is uniquely positioned to become an integral part of modern combination regimens.”
“The publication [of the Phase 1 trial results] represents the commitment to our strategy to communicate data through peer review and therefore build validation for ilixadencel within the global scientific and medical community,” said Carlos de Sousa, Immunicum’s chief executive officer. “We strongly believe in the potential of ilixadencel as an off-the-shelf immune primer in the treatment of solid tumors and are focused on advancing its clinical development to bring this therapy to patients.”