Haplo-Identical Transplants Using Post Transplant Cyclophosphamide (PTCy) Are Associated with Good Outcomes If Transplanted with Early Disease - a Single Centre Analysis from India
Authors: George Biju , Abraham Aby , Korula Anu , Devasia Anup Joseph , Lakshmi Kavitha M , N. Fouzia , Kulkarni Uday Prakash , Srivastava Alok , Mathews Vikram 
Published: October 2019

Abstract
Introduction: Haploidentical transplants are increasingly being used in patients who need a transplant but do not have a matched sibling or unrelated donor. The easy availability of a family donor makes it very attractive but it is associated with its own specific complications. We present the outcomes of haplo-identical transplants from a single centre in India
Patients and methods: We reviewed the outcomes of all patients who underwent Haplo-identical transplant at the Christian Medical College, Vellore, India between 2010 to 2017 using post transplant Cyclophosphamide (PTCY) as graft versus host disease (GVHD) prophylaxis. Data was collected from individual medical records and databases available in the department. The disease status of all patients was classified into early, intermediate and advanced disease based on a modification of the CIBMTR criteria for malignant disease. Early disease included patients transplanted in CR1 for malignant disease, patients with aplastic anemia (AA) with <20 transfusions, no active infection or exposure to immunosuppressive therapy while Intermediate disease consisted of transplant in CR2 for haematological malignancies, AA failure post ATG or > 20 transfusions and primary immunodeficiency syndromes (PID) who have had previous infection. Patients who were transplanted >CR2 or refractory disease, second transplants or presence of active infection were classified as Advanced disease.
Results: Between 2010 and 2017, 149 patients underwent 158 haplo-identical transplants. This included 101 males and 48 females with a median age of 18.1 years (range: 0.9 - 58). Seventy patients (46.9%) were children (< 15 years of age). Patients underwent transplants for both malignant (n = 85) and non-malignant (n = 73) indications. Disease status was classified as Early in 20, Intermediate in 84 and Advanced in 54. Conditioning included both myeloablative (n = 90) and non-myeloablative conditioning (n = 68) and graft source was predominantly peripheral blood stem cells (PBSC in 93%). Engraftment was seen in 90.9% while graft failure occurred in 8% and death prior to engraftment occurred in 2%. Acute GVHD was seen in 32% of evaluable patients. Infections were a major problem with bacteraemia seen in 41% (majority were gram negative) and viral infections in 68% (CMV and BK virus). The 1 year OS for the entire cohort is 44.1 + 4.1% while the 2 year OS is 39.2 + 2.1%. The 1 and 2 yr OS for early disease was 71.8 + 1.1 and 63.8 + 1.2% respectively compared to 50 + 5.8% and 48 + 5.9% for intermediate disease and 23.4 + 5.9% and 18.2 + 5.6% for advanced disease.
Conclusions: Haplo-identical transplants are feasible and associated with moderate outcomes in a developing country like India. Infectious complications are the major challenge with haploSCT and early transplantation remains the key to improving outcomes.
Figure 1 - 2 year overall survival of patients with the early, intermediate and advanced disease

Disclosures
No relevant conflicts of interest to declare.