My title today is ‘A New Anti-CD22 CAR-T Immunotherapy Saved the Lives of Children with Leukaemia.’ I’m from Beijing Boren Hospital in China.
B-acute lymphoblastic leukaemia is a fatal blast cell tumour and it is usually treated by chemotherapy and allogenic haematopoietic stem cell transplantation.
In recent studies CD19 CAR-T immunotherapy has been successfully used in treating refractory or relapsed B-acute lymphoblastic leukaemia.
However, some patients still relapsed and usually they were resistant to a secondary CAR-T cell infusion.
So we explored a humanised CD22 CAR-T immunotherapy in paediatric refractory or relapsed B-acute lymphoblastic leukaemia.
We have 15 patients in our study, all of them are children.
The children are refractory to chemotherapy.
14 children had a relapse or no response to previous CD19 CAR-T cell immunotherapy and four children had relapsed after allogenic haematopoietic stem cell transplantation.
So, in our study all heavily treated cases with refractory or relapsed B-ALL will die with current therapies.
Here is our protocol.
First we got collector from Shanghai Yake Biotechnology company and we collected patients lymphocytes from their peripheral blood.
We did the CAR vector transduction and CAR-T expansion in vitro.
After about one week for cell culture we got CD22 CAR-T cells.
So we infused the CAR-T cells into patients and after that we monitored and treated the side effects.
The major side effect is cytokine release syndrome.
After we did the evaluation of therapeutic efficacy.
The cell culture used are both in our hospital.
These are the results.
First of all we got high efficacy in our study.
The complete remission rate is 80% and the partial remission rate is 6.7%. So the overall response rate is 86.7%.
We also evaluated long-term outcomes.
We had 13 response cases and we had progression free survival rate of 91.7%.
On the other hand, we think this therapy is quite safe.
This picture showed major side effects – cytokine release syndrome in all patients.
We find now mild CRS in all patients and nobody died from our study.
Here is our conclusion.
CD22 CAR-T immunotherapy brings hope for patients with refractory or relapsed B-ALL who even fail CD19 CAR-T immunotherapy.
We think that it is quite safe, no children died and no children had severe side effects during the study.
So if anyone wants to know the details of our study, you’re welcome to our presentation.