If you or a loved one is preparing for a stem cell transplant to treat blood cancer, your health care provider may talk with you about a treatment called Tregzi (allogeneic regulatory T-cell immunotherapy with HSPC and T cells-vldq).
Tregzi is a cell therapy given as part of an allogeneic stem cell transplant. "Allogeneic" means the cells come from a donor rather than from your own body. Tregzi is made from the blood cells of a matched donor and is used to help rebuild your blood and immune system after strong cancer treatment; it also lowers the risk of a common transplant complication called chronic graft versus host disease (GvHD).
Continue reading to learn more about Tregzi for allogeneic transplant, including who it is for, how it works, how it's given, and what a clinical study found.
Is Tregzi Right for Me?
Tregzi is FDA-approved for adults with blood cancers (hematological malignancies) who are having a matched-donor stem cell transplant along with a strong pretransplant treatment called a myeloablative preparative (conditioning) regimen.
Tregzi is used to help your body rebuild blood cells and immune cells (called hematopoietic and immunologic reconstitution, respectively). It also improves chronic GvHD-free survival, which means living longer without developing moderate-to-severe chronic GvHD.
An allogeneic stem cell transplant is a major treatment. To help decide whether Tregzi and a transplant are right for you, your health care provider will consider the type of blood cancer you have, your overall health, and whether a suitable matched donor is available.
Tregzi has not been studied in children, so it is not approved for people younger than 18. If you are pregnant, planning to become pregnant, or breastfeeding, talk to your health care provider, because Tregzi has not been studied in these situations.
What Is Tregzi and How Does It Work?
Tregzi is made from cells collected from the blood of a donor whose tissue type closely matches yours (an 8/8 HLA-matched related or unrelated donor). It is prepared specifically for you and contains three different types of cells, given in separate infusion bags:
Hematopoietic stem and progenitor cells (HSPCs). These are blood-forming stem cells. After the transplant, they settle into your bone marrow and grow into all the different types of blood cells, helping restore your blood counts and immune system.
Regulatory T cells (Tregs). These immune cells help calm and control your immune system. In Tregzi, the Tregs are given to help lower the risk of GvHD, a condition in which the donor's immune cells attack the patient's healthy tissues.
Conventional T cells (Tcons). These immune cells help your new immune system fight infections and can also help fight leukemia. They are given a couple of days after the stem cells so the regulatory T cells have time to help keep the immune response in balance.
By carefully separating and timing these cell types, Tregzi is designed to help rebuild a healthy blood and immune system after transplant while reducing the chance of chronic GvHD.
How Is Tregzi Given?
Tregzi is given into a vein as an IV infusion, usually through a central venous catheter (a soft tube placed in a large vein). Each course of Tregzi is a single, patient-specific set of cells that is given over a few days as part of your transplant:
Before Tregzi: You first receive a myeloablative conditioning regimen to prepare your body for treatment. This is strong chemotherapy, sometimes with radiation, that clears out cancer cells and makes room in your bone marrow for the new donor cells.
Day 0: You receive the stem cells (HSPCs) followed by the regulatory T cells (Tregs).
Day +2 to +3: A couple of days later, you receive the conventional T cells (Tcons).
Before the infusions, you may be given medicines such as diphenhydramine and/or acetaminophen to lower the chance of a reaction. Starting the day after the Tcon infusion, you will also receive a medicine called a calcineurin inhibitor to further reduce the risk of GvHD.
Your transplant team will watch you closely during and after each infusion and will care for you throughout the transplant process.
How Was Tregzi Studied?
Tregzi was studied in a clinical trial called the Precision-T study. To learn more about possible risks, see our article on Tregzi side effects.
The study enrolled adults with blood cancers who were eligible for an allogeneic transplant. These cancers included certain acute leukemias that were in remission — acute lymphoblastic leukemia (ALL), acute myelogenous leukemia (AML), or mixed-phenotype acute leukemia — and myelodysplastic syndrome (MDS). People who had already had an allogeneic stem cell transplant were not included.
Here are some details about the study:
- In total, 187 adults were randomly assigned to receive either Tregzi or a standard (unmanipulated) donor graft. Of the 93 people assigned to Tregzi, 88 received it.
- The median (middle) age was 44 years, with ages ranging from 19 to 65. About 55% were men.
- 139 patients (74%) were White, 18 patients (10%) were Asian, three patients (2%) were Black, three patients (2%) were American Indian or Alaska Native, two patients (1%) were Native Hawaiian or Other Pacific Islander, and 22 patients (12%) had race not reported.
- Nearly everyone (98%) received a strong myeloablative conditioning regimen before transplant, based on either total body irradiation or chemotherapy.
- People were followed for up to 24 months.
The main goal of the study was to measure chronic GvHD-free survival — the length of time people lived after transplant without dying and without developing moderate-to-severe chronic GvHD. An independent group of experts reviewed cases to decide whether chronic GvHD had developed.
What Are the Main Benefits of Tregzi Based on the Study?
In the Precision-T study, people who received Tregzi were more likely to be living free of moderate-to-severe chronic GvHD than people who received a standard donor graft.
- At 12 months, an estimated 78% of people in the Tregzi group were alive and free of moderate-to-severe chronic GvHD, compared with about 38% of people in the standard-of-care group.
- By 12 months, moderate-to-severe chronic GvHD had developed in about 12.6% of the Tregzi group, compared with 44.0% of the other group.
- Deaths not related to the cancer coming back (non-relapse deaths) at 12 months occurred in about 3.4% of people treated with Tregzi, compared with 11.7% in the standard-of-care group.
- All people treated with Tregzi recovered a key type of infection-fighting white blood cell (neutrophils) within 28 days of infusion, showing that the new blood-forming cells had taken hold.
As with any transplant, the cancer can still come back. In the study, 16.1% of people in the Tregzi group and 10.6% in the standard-of-care group experienced a cancer relapse. Your health care provider can talk with you about what these results may mean for your situation.
Your results may differ from those seen in the study.
Is There Any Support or Assistance Available?
A support program for Tregzi is available through the drugmaker. This program may offer help with transportation, lodging, out-of-pocket meal costs, or other travel-related expenses for Tregzi treatment. To learn more, visit www.tregzi.com/mytregzi-support. You can reach them by phone at 877-411-ORCA (877-411-6722), then select option 4 to find out if you qualify, as financial and other eligibility requirements apply.