Professor Bart Neyns’ team has tested a new experimental treatment in which the body’s cells that help the immune system to attack and render harmless cancer cells (dendritic cells) are injected into the tumor at the same time as a additional synthetic immune-boosting agent (01B). The objective is thus to strengthen the immune response. The clinical trial focused on melanoma patients with metastases in the skin and lymph nodes into which a product could be easily injected. The treatment has proven to be safe and offers excellent results. In two of the eight patients, all metastases disappeared. The findings were presented last week at the 37th Annual Meeting of the Society of Immunotherapy of Cancer (SITC) in Boston by Dr. Jens Tijtgat. Given these promising initial results, the clinical trial will resume in 2023.
Prof. Bart Neyns, Head of the Department of Medical Oncology, explains: “Over the past decade, tremendous progress has been made in the treatment of advanced melanoma. Today, we are able to cure about 25% of these patients. Unfortunately, the disease continues to have a fatal outcome for the majority of our patients. We know that these tumor cells are not always so visible to our immune system, which is a prerequisite for current immunotherapy to work optimally. Preclinical scientific research has already shown that so-called myeloid dendritic cells (i.e. cells in the body that attack and render harmless cancer cells) play an essential role in the recognition of cancer cells and the coordination of a effective immune response against disease. It is precisely because some tumors exclude these cells that we imagined this study in which myeloid dendritic cells isolated from the blood are injected into the metastasis, along with a substance (an adjuvant) which activates these cells. We hoped to give the immune system the necessary ‘boost’ to be able to then eliminate the cancerous cells using ‘standard’ immunotherapy (which is already part of our standard treatment, but which proved to be insufficient in these patients).
The experimental treatment is safe and promising
The study focused on melanoma patients with metastasis to the skin and lymph nodes, in which one could safely prick to deliver the study drugs into the tumor.
The experimental treatment was found to be safe, and in two of the eight patients in the study, all metastases disappeared. In another patient, the tumor cells disappeared from the injected lesion and the diameter of the remaining metastases decreased by more than half, and this after only 12 weeks of treatment. Processing is currently underway.
And Professor Bart Neyns to comment: “These are very encouraging results. These study patients were doomed because standard treatments were not working. The fact that some of them are now healed has special significance. We had already obtained similar results by administering the myeloid dendritic cells at the same time as the anti-cancer virus T-VEC. Unfortunately, this development could not be continued because the T-VEC virus is no longer available in Belgium. Inspired by these first pioneering results (meanwhile published, JK Schwarze et al. JITC 2022), we decided to launch this new study and replace T-VEC with a synthetic agent (AS01B) which is 100x cheaper than T- VIC”.
Patients in whom, despite the failure of the standard treatments available, the melanoma wants to progress mainly in the skin and the lymph nodes show the best results. For these patients, this experimental therapy represents an additional opportunity for long-term improvement. Two of the patients treated in the previous clinical trial (with T-VEC and dendritic cells) have now been fully cured for over three years.
Clinical research at UZ Brussel
These promising initial results deserve further follow-up. Professor Neyns’ team is studying in detail the characteristics of melanomas that have responded favorably or not to the study treatment. By better understanding why certain tumors do not react, researchers hope to be able to develop other drugs in the future to overcome these resistance mechanisms.
The clinical trial will resume from 2023. Patients who wish to participate in clinical trials in the field of cancer can discuss this with their treating physician or contact the Oncology Center of UZ Brussel. (Tel.: 02 477 60 40 – e-mail: [email protected]).
This clinical trial is made possible thanks to the financial support of the Kom op tegen Kanker association and the Paul De Knop Fund.