Adult human mesenchymal stromal cells and the treatment of graft versus host disease.

Graft versus host disease is a difficult and potentially lethal complication of hematopoietic stem cell transplantation. It occurs with minor human leucocyte antigen (HLA) mismatch and is normally treated with corticosteroid and other immunosuppressive therapy. When it is refractory to steroid therapy, mortality approaches 80%. Mesenchymal stromal cells are rare cells found in bone marrow and other tissues. They can be expanded in culture and possess complex and diverse immunomodulatory activity. Moreover, human mesenchymal stromal cells carry low levels of class 1 and no class 2 HLA antigens, making them immunoprivileged and able to be used without HLA matching. Their use in steroid-refractory graft versus host disease was first described in 2004. Subsequently, they have been used in a number of Phase I and II trials in acute and chronic graft versus host disease trials with success. We discuss their mode of action, the results, their production, and potential dangers with a view to future application.

A phase 2 study of allogeneic mesenchymal stromal cells for luminal Crohn's disease refractory to biologic therapy.

BACKGROUND & AIMS: Transplantation of peripheral blood stem cells has been successful therapy for small numbers of patients with Crohn's disease (CD), but requires prior myeloconditioning. Mesenchymal stromal cells (MSCs) escape immune recognition, so myeloconditioning is not required before their administration. We investigated the efficacy of allogeneic MSCs in patients with luminal CD. METHODS: Our phase 2, open-label, multicenter study included 16 patients (21-55 y old; 6 men) with infliximab- or adalimumab-refractory, endoscopically confirmed, active luminal CD (CD activity index [CDAI], >250). Subjects were given intravenous infusions of allogeneic MSCs (2 × 10(6) cells/kg body weight) weekly for 4 weeks. The primary end point was clinical response (decrease in CDAI >100 points) 42 days after the first MSC administration; secondary end points were clinical remission (CDAI, <150), endoscopic improvement (a CD endoscopic index of severity [CDEIS] value, <3 or a decrease by >5), quality of life, level of C-reactive protein, and safety. RESULTS: Among the 15 patients who completed the study, the mean CDAI score was reduced from 370 (median, 327; range, 256-603) to 203 (median, 129) at day 42 (P < .0001). The mean CDAI scores decreased after each MSC infusion (370 before administration, 269 on day 7, 240 on day 14, 209 on day 21, 182 on day 28, and 203 on day 42). Twelve patients had a clinical response (80%; 95% confidence interval, 72%-88%; mean reduction in CDAI, 211; range 102-367), 8 had clinical remission (53%; range, 43%-64%; mean CDAI at day 42, 94; range, 44-130). Seven patients had endoscopic improvement (47%), for whom the mean CDEIS scores decreased from 21.5 (range, 3.3-33) to 11.0 (range, 0.3-18.5). One patient had a serious adverse event (2 dysplasia-associated lesions), but this probably was not caused by MSCs. CONCLUSIONS: In a phase 2 study, administration of allogeneic MSCs reduced CDAI and CDEIS scores in patients with luminal CD refractory to biologic therapy. ClinicalTrials.gov number, NCT01090817.

Prothrombinex-VF use in warfarin reversal and other indications.

OBJECTIVE: To assess the use of Prothrombinex-VF powder for injection (PTX-VF) at Royal Perth Hospital and analyse the efficacy and safety profile of PTX-VF. DESIGN, SETTING AND PATIENTS: A prospective observational audit of PTX-VF use, conducted by reviewing medical records and laboratory and imaging results for all patients prescribed PTX-VF from 1 November 2009 to 1 May 2010. MAIN OUTCOME MEASURES: Data on indication, diagnosis, comorbidities, dose of PTX-VF, fresh frozen plasma (FFP) and vitamin K, coagulation parameters before and after PTX-VF administration, and adverse effects. RESULTS: 334 vials of PTX-VF were administered to 84 patients over 107 prescriptions. Indications were warfarin reversal, intraoperative bleeding and coagulopathy (66, 20 and 21 prescriptions, respectively). PTX-VF with FFP was compared with PTX-VF alone for warfarin reversal and there was a significant decrease in international normalised ratio (INR) that was independent of group (P < 0.001). Lower doses of PTX-VF (< 25 IU/kg) were compared with higher doses (25-50 IU/kg) for warfarin reversal and decrease in INR was significant, independent of group (P = 0.002). PTX-VF was administered for intraoperative bleeding in 18 patients who had not been treated with warfarin. No hypersensitivity reactions, thrombotic complications or worsening of disseminated intravascular coagulation occurred during 7-day follow-up. CONCLUSION: For warfarin reversal, lower doses of PTX-VF (< 25 IU/kg) and PTX-VF without FFP were effective. PTX-VF was also used in intraoperative bleeding and non-warfarin coagulopathy. No adverse events were associated with PTX-VF.