The poten­tial new multiple myeloma ther­apy ECT-001 has been designated a Regenerative Medicine Advanced Therapy (RMAT) by the U.S. Food and Drug Admin­istra­tion (FDA).

The RMAT desig­na­tion is very similar in sig­nif­i­cance to the better known Break­through Therapy desig­na­tion, which also is granted by the FDA. Both the RMAT and Break­through Therapy desig­na­tions are in­tended to shorten the time it takes im­por­tant new ther­a­pies to gain FDA mar­ket­ing approval.

The key dif­fer­ence be­tween the two desig­na­tions is that the RMAT desig­na­tion is for cell-based ther­a­pies, while the Break­through Therapy desig­na­tion is for drug-based ther­a­pies.

ECT-001 consists of what are known as “expanded cord blood stem cells.” Patients who are treated with ECT-001 undergo the equivalent of a standard allo­geneic (donor) stem cell trans­plant, except that expanded cord blood stem cells are used during the trans­plant instead of stem cells from adult donors.

Cord blood stem cells are stem cells harvested from the blood present in umbilical cords and pla­centas. Such blood is often collected after babies are born, after which it is stored in cord blood banks.

Expanded cord blood stem cells are cord blood stem cells that have been cul­tured and en­cour­aged to replicate (“expand”) in sig­nif­i­cant numbers.

An im­por­tant upside of cord blood stem cells is that using them during allo­geneic stem cell trans­plants has been shown to reduce the risk and severity of graft-versus-host disease (GVHD), a serious, some­times fatal, com­pli­ca­tion of allo­geneic trans­plants.

The downside to cord blood stem cells is that the number of them avail­able to be admin­istered to a patient during a trans­plant is much lower than is the case with stem cells from non-cord blood sources. As a result, patients receiving cord blood stem cell trans­plants must wait longer after trans­plan­ta­tion for their blood counts to return to normal levels, leaving them at greater risk for in­fec­tion

By using expanded cord blood stem cells, researchers can trans­plant patients with a greater number of stem cells, with the goal of reducing post-transplant in­fec­tion risk while still providing patients the benefits asso­ci­ated with cord blood stem cell trans­plan­ta­tion.

The RMAT desig­na­tion for ECT-001 is for the treat­ment of blood cancers, in­­clud­ing multiple myeloma. Results of an initial clin­i­cal trial of ECT-001 in blood cancer patients were presented at the 2018 American Society of Hematology (ASH) annual meeting (abstract), and a trial testing ECT-001 in high-risk newly diag­nosed multiple myeloma patients is ongoing in Montreal, Quebec.

ExCellThera Inc., the Canadian com­pany that is devel­op­ing ECT-001, announced the ECT-001 RMAT desig­na­tion in a press release issued last week.

ECT-001 is only the second poten­tial new myeloma ther­apy cur­rently known to have been granted an RMAT desig­na­tion. Last November, Poseida Therapeutics announced that P-BCMA-101, a chi­meric an­ti­gen re­cep­tor (CAR) T-cell ther­apy it is devel­op­ing as a poten­tial treat­ment for multiple myeloma, had been granted an RMAT desig­na­tion by the FDA (related press release).

(The FDA does not publicly announce RMAT desig­na­tions, and com­pa­nies are not legally required to report the desig­na­tion beyond any obli­ga­tion they may have as a result of financial reporting reg­u­la­tions.)

More About ECT-001 And Cord Blood Stem Cells

ECT-001 cells are produced by placing cord blood stem cells for seven days in a medium that con­tains UM171, a pro­pri­e­tary com­pound devel­oped by ExCellThera explicitly for the pur­pose of en­cour­ag­ing the replication (expansion) of cord blood stem cells.

In the clin­i­cal trial of ECT-001 whose results were reported at last year’s ASH meeting, exposing cord blood stem cells to UM171 over the course of a week led to a median 35-fold in­­crease in the number of stem cells avail­able to be admin­istered to each trial par­tic­i­pant.

This in­­creased stem cell dose is the goal of the expansion process, as it should help reduce the period of time after trans­plan­ta­tion that patients receiving the stem cells have very low white blood cell counts. This, in turn, should reduce the risk of serious in­fec­tion during that time.

More About RMAT Desig­na­tions

RMAT and Break­through Therapy desig­na­tions both make it possible for com­pa­nies to have earlier, more frequent, and more senior-level inter­actions with the FDA about the qualifying ther­a­pies. The desig­na­tions also allow com­pa­nies to submit approval appli­ca­tions for the ther­a­pies on a rolling basis, rather than having to wait until all in­for­ma­tion for an appli­ca­tion is avail­able before it can be submitted.

For a cell-based ther­apy to qualify for an RMAT desig­na­tion, it must be in­tended to treat, modify, reverse, or cure a serious disease or con­di­tion, and there must be pre­lim­i­nary clin­i­cal evi­dence that the ther­apy addresses an unmet medical need related to the disease or con­di­tion.