Allogeneic Cytokine-induced Killer Immunotherapy for Relapse After Allogeneic Marrow Transplant for Haematological Malignancies

• Patient inclusion criteria This trial includes only patients who have relapsed after an allogeneic transplant, who have either 1.1 No response to conventional DLI given for at least one dose, or 1.2 No possibility of access to large number of donor lymphocyte for repeated doses of DLI, This applies to cases of unrelated transplant or cord blood transplant

1,3 Patients who developed significant GVHD to conventional DLI, but had no other therapeutic option. In such cases the rationale is based on mice studies of mismatched CIK producing much less GVHD than mismatched unmanipulated splenocytes.

• Collection of peripheral blood stem cells ( PBSC ) Sibling allogeneic donors will routinely have their PBSC harvested for the purpose of infusion into the recipients. Currently our practice involves one additional day of collection to freeze as backup to be used for DLI in the event of relapse. This collection is frozen in a few aliquots, and is available for CIK culture when need arises

For cord blood transplant, one issue is that DLI is not available. There is one report on growing CIK from residual cells in the bags of cord blood after infusion, then stored frozen for use in future if need arises. This does not in anyway compromise the cord blood infusion. Similarly this can be done in the case of unrelated donor transplant. This will serve as a backup in the event that donor is not available for repeat collection of lymphocyte.

• Culture of CIK cells

For culture from frozen product, this is rapidly thawed and culture started in gas permeable bags in complete medium and cytokine as detailed in SOP attached ( appendix 1 ). Culture medium and cytokine are added periodically till maturation of CIK at between 21-28 days.

For culture from residual cells in the thawed cord blood infusion bags, cells may need to undergo ficoll to remove rbc, then start culture in the similar way

• Harvesting of CIK cells

At maturity between D21-D28, all bags of CIK cells are pooled and washed using COBE 2991 cell harvester. This will ensure removal of >99.9% of the original culture medium. Cells are then frozen and aliquots sent for quality control to ensure compliance to GMP standard. This includes bacteriological and fungal culture, mycoplasma and endotoxin testing.

• Infusion of CIK cells Patients may undergo cytoreductive chemotherapy or oral immunosuppressive therapy as deemed fit in each individual case by the attending physician. At the nadir of lymphopenia , CIK cells are rapidly thawed at bedside and infused.

Dose and schedule of CIK cells follows the following principle 4.1 First dose for patients who have already received DLI and showed resistance : at double or triple the last DLI dose ( expressed as CD3/kg ).

4.2 First dose for patients who have not received any DLI : this will follow the conventional practice of DLI where the first dose will be 10 million CD3/kg.

4.3 Subsequent doses will be given at 4-weekly intervals allowing time to observe for development of GVHD and response.

4.3.1 If no response was observed, dose will be doubled or tripled ( depending on the size of the available aliquot ). If there is good response, dose will remain the same as the previous infusion.

4.3.2 In the presence of GVHD, infusion will be withheld till resolution of GVHD, then resumed at half or one-third of the previous dose ( depending on the size of the available aliquot).

4.4 Duration of CIK infusion will depending on the response status 4.4.1 In responding patients, 4-weekly CIK infusion will continue till a complete remission is achieved and then another 2-3 infusions beyond.

4.4.2 In patients who achieve a stable partial response, CIK infusion will continue in a 4-weekly interval, provided no adverse effect and CIK cells are available. This will continue on and stop if disease breaks through.

4.4.3 In patients where disease continues to progress after 2-3 cycles of CIK infusion, no further infusion will be given

Inclusion criteria

This trial includes only patients who have relapsed after an allogeneic transplant, who have either:

• No response to conventional DLI given for at least one dose, or
• No possibility of access to large number of donor lymphocyte for repeated doses of DLI, This applies to cases of unrelated transplant or cord blood transplant
• Patients who developed significant GVHD to conventional DLI, but had no other therapeutic option. In such cases the rationale is based on mice studies of mismatched CIK producing much less GVHD than mismatched unmanipulated splenocytes.

In view of the period taken to culture the cell to maturity, patient must have a life expectancy of more than one month. Interim measures eg chemotherapy or conventional DLI will be given during the interval so that ongoing treatment will not be compromised in any way.

Exclusion criteria

• Uncontrolled infection or significant bleeding
• Unstable vital signs
• Any degree of hypoxia requiring oxygen therapy.