Haploidentical Hematopoietic Stem Cell Transplantation in Leukemia's: Experience from a Cancer Center in India

Initiation of Haploidentical Stem Cell Transplantation With Post-Transplant Cyclophosphamide in Children: A Low-Middle-Income Country Institutional Experience

BACKGROUND

Haploidentical hematopoietic stem cell transplant (HSCT) is a curative treatment especially for countries where bone marrow registries are nonexistent. We present our experience with haploidentical HSCT in pediatric patients.

METHODS

Retrospective data collected and analyzed for patients ≤18 years, from January 2017 to December 2022.

RESULTS

The cohort consisted of 20 patients with median age at transplant of 61.5 (IQR: 124) months. Fourteen (70%) were malignant and 6 (30%) were benign diseases. Donors were father in majority (9/20; 45%). Stem cell source was peripheral blood 8, marrow 8, and combined 4. c-specific antibodies were positive in 6 (30%). Median CD34 cell dose infused: 9.35 × 106/kg. Median engraftment time: 15 (IQR: 17) days. Acute and chronic graft-versus-host disease (GVHD) occurred in 12/20 (60%) and 5/20 (25%), respectively. Complications included infection/sepsis (14/20; 70%), cytomegalovirus reactivation (14/20; 70%), sinusoidal obstruction syndrome (1/20; 5%), primary graft failure (PGF) (6/20; 30%), and secondary graft failure (4/20; 20%). PGF was more common in benign conditions (p = 0.003) and less prevalent in cases with aGVHD (p = 0.007). aGVHD was more common in malignant conditions (p = 0.007). Overall survival (OS), relapse-free survival (RFS), and treatment-related mortality (TRM) were 40%, 50%, and 35%, respectively. Median time of survival and relapse were 8 (IQR: 15) and 9 (IQR: 13) months, respectively.

CONCLUSION

OS was comparable to that of other low-middle-income countries. GVHD was a major challenge, along with sepsis and CMV infection. Half of the leukemias relapsed. Graft failure was a major concern in nonmalignant diseases.

Haploidentical Stem Cell Transplantation: Half Match but More Hope!-Single Centre Experience from Western India

With the success of post-transplant cyclophosphamide based platform and improved clinical care, the number of haploidentical stem cell transplants (HaploSCT) have surged over the last decade. However, data from India is scarce. We aimed to evaluate the outcome of haploSCT at our centre. Since the inception of government schemes, many patients at our centre are able to undergo transplantation at subsidized cost. We conducted a retrospective analysis of the haploidentical transplants performed between January 2015 and November 2022. Fifty patients were eligible for this study. Patient details were obtained from case files. The graft versus host disease (GVHD) prophylaxis was post-transplant Cyclophosphamide (PTCy) with Mycophenolate-mofetil and Cyclosporine/tacrolimus/sirolimus. All patients were transfused peripheral blood stem cells from donors. Post-transplant, patients continued regular follow up as per schedule. Supportive care was given as per unit protocol. Overall survival (OS) was calculated using the Kaplan-Meier method. Fifty patients underwent haploSCT. A total of fifty patients with a median age of 20 years (range 3-53 years) underwent haploidentical HSCT from a family donor. Twenty three (46%) patients were > 18 years age and 82% were males. Indications for transplant included both benign and malignant hematological diseases. Most common conditioning regimen used was Fludarabine + Busulphan + Cyclophosphamide (n = 38, 76%). Thirty five patients (70%) engrafted successfully. In the patients who had successful engraftment, the median time to neutrophil engraftment was 16 days (range 10-20 days) and platelet engraftment was 18 days (range 10-32). Fourteen patients developed acute GVHD (28%), and three patients developed chronic GVHD (6%). The median follow-up was 30 months and the two-year OS was 43% with a median OS of 17 months. Twenty-one (adult = 9, pediatric = 12) out of 50 patients (42%) are alive and on regular follow-up. HaploSCT with a PTCy platform is a cost-effective, promising modality of treatment in patients who have no suitable matched donors and are not affording matched unrelated transplants. At our centre, we were able to achieve acceptable results with use of generic medications at affordable cost. Transplant Related Mortality (TRM) rates were comparable to other centres, however, multi-drug resistant bacterial infection remains a challenge in performing haploidentical HSCT in developing countries.

Fludarabine melphalan versus fludarabine treosulfan for reduced intensity conditioning regimen in allogeneic hematopoietic stem cell transplantation: a retrospective analysis

Various reduced-intensity conditioning (RIC) regimens are used to decrease toxicity while providing comparable outcomes to myeloablative regimens. We compared toxicity and outcomes between two RIC regimens, fludarabine with melphalan (Flu-Mel) and fludarabine with treosulfan (Flu-Treo), retrospectively over a 10-year period in two donor groups, matched related donor (MRD)/matched unrelated donor (MUD) and haploidentical (Haplo) transplants. The study included 138 patients, of which 105 received MRD/MUD (Flu-Mel: 94, Flu-Treo: 11) and 33 Haplo (Flu-Mel: 17, Flu-Treo: 16) transplants. In the MRD/MUD group, 44 (47%) of patients who received Flu-Mel had grade 3/4 oral mucositis compared to 1 (9%) who received Flu-Treo (P = 0.02). Corresponding numbers in the Haplo group were 7 (41%) and 1 (6%). Grade 3/4 diarrhoea was more frequent with Flu-Mel than Flu-Treo in the Haplo group (41% vs 6%; P = 0.039), but not the MRD/MUD group. Median follow-up time for all patients was 4.8 years. Five-year OS in the MRD/MUD group was 62% with Flu-Mel versus 53% with Flu-Treo (P = 0.0694). Similarly, 5-year OS was 41% with Flu-Mel and 28% with Flu-Treo (P = 0.770) in the Haplo group. Severe mucositis and diarrhoea were significantly less frequent with Flu-Treo than Flu-Mel. Flu-Treo provided comparable outcomes to Flu-Mel in all donor transplants.

Assignment of the antibacterial potential of Ag2O/ZnO nanocomposite against MDR bacteria Proteus mirabilis and Salmonella typhi isolated from bone marrow transplant patients

The rate of infectious diseases started to be one of the major mortality agents in the healthcare sector. Exposed to increased bacterial infection by antibiotic-resistant bacteria became one of the complications that occurred for bone marrow transplant patients. Nanotechnology may provide clinicians and patients with the key to overcoming multidrug-resistant bacteria. Therefore, this study was conducted to clarify the prevalence of MDR bacteria in bone marrow transplant recipients and the use of Ag2O/ZnO nanocomposites to treat participants of diarrhea brought on by MDR bacteria following bone marrow transplantation (BMT). Present results show that pathogenic bacteria were present in 100 of 195 stool samples from individuals who had diarrhea. Phenotypic, biochemical, and molecular analysis clarify that Proteus mirabilis and Salmonella typhi were detected in 21 and 25 samples, respectively. Successful synthesis of Ag2O/ZnO nanocomposites with a particle enables to inhibition of both pathogens. The maximum inhibitory impact was seen on Salmonella typhi. At low doses (10-5 g/l), it prevented the growth by 53.4%, while at higher concentrations (10-1 g/l), Salmonella typhi was inhibited by 95.5%. Regarding Proteus mirabilis, at (10-5 g/l) Ag2O/ZnO, it was inhabited by 78.7%, but at higher concentrations (10-1 g/l), it was inhibited the growth by 94.6%. Ag2O/ZnO nanocomposite was therefore found to be the most effective therapy for MDR-isolated bacteria and offered promise for the treatment of MDR bacterial infections that cause diarrhea.

Hematopoietic cell transplantation landscape in India

Hematopoietic cell transplantation (HCT), commonly known as Bone marrow transplantation (BMT), is a medical procedure used to treat various conditions, including blood cancers, genetic disorders, and certain autoimmune diseases. The procedure involves replacing damaged or diseased bone marrow with healthy stem cells to promote the production of new, healthy blood cells. In India, HCT has been performed for several years in specialized medical centers. India has a growing healthcare infrastructure, and many hospitals are equipped to perform these procedures. Though there are studies on HCTs done at individual transplant centers in India, a comprehensive analysis of the current landscape of HCT in the country is lacking. HCT in India has seen major advances both in the quantity and quality of HCT centers. This review article has attempted to cover the gaps of HCT in India, including its status in the Armed Forces HCT centers.

Bone marrow transplant: A two-decade single centre hematology experience

Background

Bone Marrow Transplant (BMT) is a curative form of therapy for many hematological disorders in both the adult and pediatric patients. The availability of BMT in the AFMS at AHRR for the last 02 decades has been a game changer for the patients.

Methods

We reviewed our BMT data since the inception of the program till Feb 2023.

Results

Over 700 patients with more than 23 different types of hematological disorders have undergone this procedure 58%% patients underwent an Autologous BMT and 42% an allogenic BMT. Autologous BMT for Multiple Myeloma and Allogenic BMT for Aplastic Anemia and Acute Leukemias have been the most common indications. 73% patients were adults, and 27% patients were of the pediatric age group. The male: female ratio was 2:1. The spectrum of allogenic Hematopoietic Stem Cell Transplant (HSCT) has expanded from Matched Sibling Donor (MSD) transplants to Matched Unrelated Donor (MUD) Transplants and Haploidentical Donor Transplants. 93% of our Allogenic BMT patients underwent a MSD BMT, 1% MUD BMT and 06% Haploidentical BMT. Today no patient with a malignant hematological disorder requiring a BMT is denied the procedure due to the lack of an HLA donor due to the availability of haploidentical BMT.

Conclusion

The evolution of a BMT program has a long learning curve and the expanded pool of eligible donors has led to a situation of "transplant for all". Haploidentical HSCT for nonmalignant hematological disorders is an unmet need. CART cell therapy and Cellular therapies need to be prioritized for future inclusion.

Two-drug versus three-drug induction chemotherapy in pediatric acute myeloid leukemia: a randomized controlled trial

The benefit of three-drug induction chemotherapy over a two-drug induction has not been evaluated in pediatric acute myeloid leukemia (AML). We, therefore, conducted a randomized controlled trial to ascertain the benefit of a three-drug induction regimen. Patients aged 1–18 years with newly diagnosed AML were randomized to two cycles of induction chemotherapy with daunorubicin and ara-C (DA) or two cycles of ara-C, daunorubicin, and etoposide (ADE). After induction, patients in both arms received consolidation with two cycles of high-dose ara-C. The study’s primary objective was to compare the event-free survival (EFS) between the two arms. The secondary objectives included comparing the composite complete remission (cCR) rates, overall survival (OS), and toxicities. The study randomized 149 patients, 77 in the DA and 72 in the ADE arm. The median age was 8.7 years, and 92 (62%) patients were males. The median follow-up was 50.9 months. The cCR rate in the DA and ADE arm were 82% and 79% (p = 0.68) after the second induction. There were 13 (17%) induction deaths in the DA arm and 12 (17%) in the ADE arm (p = 0.97). The 5-year EFS in the DA and ADE arm was 34.4% and 34.5%, respectively (p = 0.66). The 5-year OS in the DA and ADE arms was 41.4% and 42.09%, respectively (p = 0.74). There were no significant differences in toxicities between the regimens. There was no statistically significant difference in EFS, OS, CR, or toxicity between ADE and DA regimens in pediatric AML. The trial was registered with the Clinical Trial Registry of India (Reference number: CTRI/2014/11/005202).