Risk-stratified Sequential Treatment of Post-transplant Lymphoproliferative Disease (PTLD) With Rituximab SC and Immunochemotherapy

Summary

Post-transplant lymphoproliferative disorders (PTLD) differ clinically from lymphoma in the general (immunocompetent) population due to their higher incidence and their frequent association with Epstein-Barr virus. Previous clinical trials have shown their remarkably good response to rituximab as well as to chemotherapy.

The PTLD-1 trial demonstrated the efficacy and safety of sequential immunochemotherapy with 4 courses of rituximab IV followed by 4 cycles of CHOP chemotherapy. Compared to trials of rituximab monotherapy in PTLD, median overall survival was extended from 2.4 to 6.5 years. Compared to previous trials of chemotherapy, complications were reduced. In addition, we noted that those patients who already had a good response to the first four cycles of rituximab did better overall than those who did not. As a consequence, the PTLD-1/3 trial introduced risk-stratification in sequential treatment according to the response to the first 4 courses of rituximab monotherapy. Those patients with a complete remission went on to receive four further courses of rituximab whereas those who did not received rituximab and CHOP chemotherapy. Interim results have demonstrated that it is safe to restrict chemotherapy treatment in this manner and thus established the concept of treatment stratification based on the response to rituximab.

The PTLD-2 trial is the next step in the development of this strategy. Compared to the PTLD-1/3 trial, the key difference is the use of subcutaneous instead of intravenous rituximab application. Interim results from an ongoing trial of patients with follicular lymphoma (NCT01200758) have shown that subcutaneous administration results in increased blood levels and in non-inferior remission rates. Furthermore, the stratification strategy is refined based on observations from the previous PTLD-1 and PTLD1/3 trials: Risk groups are now defined not only based on response to rituximab therapy but also on the international prognostic index (IPI, a well-established lymphoma risk score) and the transplanted organ. The major advantage of this new stratification is an extended low-risk group that is eligible for subcutaneous rituximab monotherapy: Patients with a low risk of disease progression, defined as those who achieve a complete remission after the first four courses of subcutaneous rituximab monotherapy and those with an IPI of 0 to 2 who achieve a partial remission at interim staging, will go on with rituximab monotherapy. Patients with high IPI who achieve a partial remission, patients with stable disease at interim staging and non-thoracic transplant recipients with progressive disease at interim staging will be considered high risk. These patients will go on with 4 cycles of rituximab plus CHOP chemotherapy similar to the PTLD-1/3 protocol. Thoracic transplant recipients refractory to rituximab will be considered very high risk and will go on with rituximab subcutaneous plus alternating chemotherapy with CHOP and DHAOx.

The trial hypothesis is that the new protocol will improve the event-free survival, a measure integrating unfavorable events such as death, disease progression and treatment complications, particularly infections, in the low risk-group compared to the results of the PTLD-1 trial. In very high-risk patients data from the PTLD-1 and PTLD-1/3 trial have shown that the current treatment is not sufficient to control the disease. Death due to disease progression was observed in more than 80% of patients. Here, rituximab combined with alternating chemotherapy cycles of CHOP and DHAOx (+GCSF) may increase treatment efficacy with an acceptable toxicity profile.

In summary, the PTLD-2 trials tests if the substitution of subcutaneous for intravenous rituximab and an updated stratification strategy that deescalates treatment for those at low risk and escalates treatment for those at very high risk can further improve the overall efficacy and safety of PTLD therapy.

Conditions

• Posttransplant Lymphoproliferative Disorder

Interventions

DRUG

Rituximab sc

All patients will receive 4 courses of rituximab on days 1, 8, 15 and 22. Rituximab will be administered as a single therapeutic agent at a standard dosage of 375 mg/m2 infused intravenously at day 1. Three subsequent single therapeutic agent applications of rituximab will be administered subcutaneously at a fixed dose of 1400 mg once a week for 3 weeks at days 8, 15 and 22.

DRUG

Rituximab sc consolidation

Patients considered low-risk will receive four more single therapeutic agent applications of rituximab administered subcutaneously at a fixed dose of 1400 mg once every three weeks at days 50, 71, 92 and 113.

DRUG

Rituximab sc combined with CHOP chemotherapy

Patients considered high-risk will receive four more applications of rituximab administered subcutaneously at a fixed dose of 1400 mg combined with CHOP chemotherapy every 3 weeks at days 50, 71, 92 and 113. CHOP chemotherapy will be administered at standard doses: cyclophosphamide 750 mg/m2, adriamycine 50 mg/m2, vincristine 1.4mg/m2 (maximum total dose: 2mg) and prednisone 100mg (at day 1 to 5 of each cycle). Cyclophosphamid, adriamycine and vincristine will be infused intravenously. Prednison will be administered orally in a single dose. At day 3-4 of each treatment cycle either a single dose of 6 mg Peg-GCSF or repetitive doses of 5 µg/kg GCSF until recovery of WBC will be applied subcutaneously, as per institutional practice.

DRUG

Rituximab sc combined with alternating chemotherapy with CHOP and DHAOx

Patients considered very high-risk will receive six more applications of rituximab sc at a fixed dose of 1400 mg combined with chemotherapy every 3 weeks. Chemotherapy is CHOP at days 50, 92 and 134 (cyclophosphamide IV 750 mg/m2, adriamycine IV 50 mg/m2, vincristine IV 1.4mg/m2 (maximum total dose: 2mg) and prednisone PO 100mg (at day 1 to 5 of each cycles). Chemotherapy is DHAOx at days 71, 113 and 155 (oxaliplatin (130 mg/m2, day 1) and cytarabine (ARA-C, 2x 1000 mg/m2 at day 2) dexamethasone PO (40 mg/m2, day 1)), as per institutional practice. At day 3-4 of each treatment cycle either a single dose of 6 mg Peg-GCSF or repetitive doses of 5 µg/kg GCSF until recovery of WBC will be applied subcutaneously, as per institutional practice.

Sponsors & Collaborators

• Diako Ev. Diakonie-Krankenhaus gemeinnützige GmbH

  lead OTHER

Principal Investigators

• Ralf U Trappe, Dr. med.- · DIAKO Bremen

Study Design

Allocation

NON_RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2015-02-03

Primary Completion

2021-07-13

Completion

2022-07-13

Countries

• Germany

Study Locations