The FDA has cleared GT Biopharma’s investigational new drug (IND) software for GTB-5550, a pure killer (NK) cell engager remedy for the potential remedy of with relapsed or refractory (r/r) CD33 expressing hematologic malignancies, together with acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (MDS).The corporate anticipates initiating the trial in second half of 2024.1
“FDA clearance for GTB-3650 is an incredible accomplishment and we sit up for submitting our subsequent IND within the first quarter of 2025 for GTB-5550, which can goal a number of stable tumors”, Michael Breen, Government Chairman and Interim Chief Government Officer, GT Biopharma, stated in an announcement.1 “As we ramp up our scientific actions, we plan to start out the Part 1 trial with GTB-3650 within the coming months adopted by a number of information readouts in 2025. We additionally anticipate to start out a basket trial with GTB-5550 for a number of stable tumors in 2025 and stay very enthusiastic in our pursuit of extra alternatives for numerous autoimmune indications the place our TriKE’s could have therapeutic utility.”
GTB-3650 is a second technology nanobody NK cell engager(TriKE) remedy. It’s a tri-specific molecule composed of a camelid nanobody that binds the CD16 receptor on NK cells, a single chain variable fragment (scFv) that acknowledges CD33 on tumor cells, and human IL-15. It adopted the corporate’s first-generation TriKE remedy for a similar indications, GTB-3550. GTB-3550 is a single-chain, tri-specific scFv recombinant fusion protein conjugate composed of the variable areas of the heavy and lightweight chains of anti-CD16 and anti-CD33 antibodies and human IL-15. GTB-3550 was evaluated in a first-in-human Part 1 scientific trial in sufferers with AML and MDS. The remedy was well-tolerated after which discontinued in favor of the second-generation iteration. GT Biopharma beforehand submitted the IND for GTB-550 in December 2023.2
WATCH NOW: Rawan Faramand, MD, on Evaluating Orca-T in Sufferers With Acute Myeloid Leukemia
“GTB-3650 is designed to focus on NK cells throughout the immune system to doubtlessly overcome lots of the limitations of present AML chemotherapies,” Breen added.1 “Our trial design ought to give us an early learn on security and potential therapeutic exercise and in addition present precious learnings that we are able to translate into our scientific improvement plans for follow-on TriKE molecules, together with GTB-5550.”
The part 1, dose escalation examine will enroll as much as 6 cohorts of grownup sufferers with r/r CD33+ hematologic malignancies, together with AML and excessive danger MDS. Individuals will obtain GTB-3650 in 2-week blocks, 2 weeks on and a pair of weeks off, for as much as 4 months relying on scientific profit. The trial will primarily be assessing security and tolerability. Different elements that will probably be assessed embody pharmacokinetics, pharmacodynamics, and in vivo enlargement of endogenous affected person NK cells and scientific exercise.1
“We sit up for advancing GTB-3650 for remedy of CD33+ leukemia. We’re excited to expeditiously transfer this molecule into the clinic as we execute on our scientific targets in 2024,” Breen stated in an earlier assertion.2
Different applications in GT Biopharma’s pipeline embody GTB-5550, a TriKE concentrating on B7H3 constructive stable tumors, which is presently in IND-enabling research. In earlier analysis phases are a PD-L1–concentrating on TriKE, GTB-4550, and a HER2-targeting TriKE, GTB-6550, each for stable tumor indications.
