Ignacio Melero

CAR-T cell-based treatments have been successful against some blood tumours, but are much less effective for solid tumours. A phase 1 clinical trial has tested their use in 11 children and young adults with diffuse midline glioma, a tumour of the nervous system that is considered incurable. The results, published in the journal Nature, indicate that the treatment improved functional status in nine of the 11 patients. One of the four who showed a strong response is still healthy four years later.

The regulatory agencies for medicines in the United States and Europe have issued statements informing about a possible risk of developing certain types of tumors following CAR-T cell immunotherapy treatment. What do we know so far? What is the real risk? Does the benefit-risk balance still hold? Has anything changed after these alerts? We answer these questions with expert opinions and the data currently available. 

CAR-T cell therapies may, in some cases, produce tumours secondary to treatment. A few months ago, the US Food and Drug Administration (FDA) said it was assessing this risk. Now, a study conducted at Stanford University Medical Center (USA) has tracked 724 patients who received this type of treatment since 2016. Of these, 14 developed another blood tumour, but only one was a T-cell lymphoma that could be a direct consequence of the therapy. Further analysis ruled out this link. The results are published in the journal NEJM. 

A multidisciplinary study involving several Spanish research groups has preclinically tested a new type of immunotherapy for multiple myeloma. Instead of modifying T cells to attack the tumour directly, as CAR-T cells do, they have managed to make them secrete bispecific antibodies, which bind to the tumour on one side and to other T cells on the other, attracting them to the tumour. According to the authors, this cell therapy was more effective than traditional CAR-Ts and could generate less resistance. The results are published in the journal Science Translational Medicine. 

The US Food and Drug Administration (FDA) has issued a statement reporting that it has received reports of T-cell tumours in patients who received various CAR-T cell treatments. As quoted in the statement, "although the overall benefits of these products continue to outweigh their potential risks for their approved uses, FDA is investigating the identified risk of T cell malignancy with serious outcomes, including hospitalization and death, and is evaluating the need for regulatory action".

A team of scientists led by the University Hospital Zurich (Switzerland) has tested a new treatment for glioblastoma, a highly aggressive nervous system tumour with a poor prognosis. The therapy consists of a fusion protein that combines the TNF factor - a key factor in the processes of inflammation and immune response - with an antibody that targets the tumour matrix. The researchers, whose results are published in the journal Science Translational Medicine, have studied its action together with a type of chemotherapy both in mice and in six patients included in a phase 1 clinical trial.

A phase 1 clinical trial has tested personalised mRNA vaccines against the most common type of pancreatic cancer with a particularly poor prognosis. The treatment, which is tailored to the characteristics of each patient's tumour, was given to 16 people along with surgery, chemotherapy and other immunotherapy. Half of them showed an immune response to the vaccine, which was associated with a better prognosis. The results are published in the journal Nature.

A phase 2 clinical trial has analysed the safety and efficacy of adding immunotherapy to traditional chemotherapy to treat a subtype of acute lymphoblastic leukaemia in children under one year of age. This subtype of leukaemia, although rare in absolute terms, is the most common in children of this age, and its prognosis in this age group had not improved in recent years. The immunotherapy used, a bispecific antibody that binds to tumour cells on the one hand and T lymphocytes on the other, improved two-year survival from 66% to 93% in treated patients, according to The New England Journal of Medicine (NEJM).

News of cancer vaccines proliferate in the media, yet only one such vaccine has been approved - against metastatic prostate cancer - and is no longer in use. However, only one as such has been approved - against metastatic prostate cancer - and it is no longer in use. Are the attention and hopes justified? What do they consist of and how are they similar to traditional ones? Are they preventive or therapeutic? Can they be universal or will they be extremely personalised? How much will they cost? This is what we know today.

Two preclinical studies published in the journal Science have introduced new bioengineered modifications to CAR-T cells in an attempt to make them more potent and safer in their anti-tumour action. These variations allow their activity to be enhanced only in the vicinity of the tumour or their actions to be regulated on demand.