Abstract
Several studies have proved the efficacy of genetically modified autologous advanced therapy medicinal products - chimeric antigen receptor T cell therapy (CAR-T) in treatment of malignant lymphoma. The first products were authorised for use in the European Union in 2018.
Investigational products for treatment of multiple myeloma are used within clinical trials, now. Collection of the starting material, concentrate of peripheral blood mononuclear cells (PBMC), is performed in the Tissue Establishment under strictly non-profit conditions.
Some manufacturers prefer sending the collected material at temperatures above zero (+2 to +8 °C), while others prefer sending of the cryopreserved cell concentrate. The final European Medicines Agency (EMA) authorized cell drug available at the market is usually cryopreserved and must be stored and transported at temperatures compliant with the instruction of the manufactures.
The authors demonstrate the cold chain from cryopreservation of starting material for tisagenlecleucel (Kymriah, Novartis) manufacturing till its storage as a final product. The respective cryopreservation protocol used for starting material is based on a combination of dimethyl sulfoxide (DMSO) with hydroxyethyl starch supplemented by human serum albumin and slow controlled cooling rate in cryobags housed in metal cassettes, which achieves the PBMC post-thaw viability of 99.2 +- 0.61 % and CD3+ recovery of 89.6 +- 5.96 %.
The final product (bags of the volume of 50 mL) housed in metal cassettes is stored in a "dry-storage" liquid nitrogen container used exclusively for registered and investigational CAR-T therapy products. The storage high temperature alarm is adjusted to -160 °C.
Transport to the clinical department is performed in the dry shipper at a temperature below -150 °C. After the product removal from the metal cassette, it is inserted into a sterile plastic bag, thawed in a 37 °C water bath and immediately infused.
This cold chain fully meets manufacturer's requirements and has been used till now in 5 patients. The genetic safety requirements are met as well.