GenFleet Announces GFH009 Granted with FDA Orphan Drug Designation for Treatment of Acute Myeloid Leukemia

Oct 12, 2023

GenFleet Therapeutics, a clinical-stage biotechnology company developing cutting-edge therapies in oncology and immunology, announced that U.S. Food and Drug Administration (FDA) has granted Orphan Drug Designation (ODD) for SLS009 (GFH009) for the treatment of acute myeloid leukemia (AML). This designation was supported by data from the phase 1, multi-center trial of GFH009 which met all key study objectives.

Preliminary results from GFH009 monotherapy study for relapsed/refractory hematological malignancies demonstrated favorable safety/tolerability of GFH009 with no unexpected dose limiting toxicities or hematological toxicities difficult to determine in patients. With regard to efficacy, the study exhibited GFH009’s anti-tumor activity of up to 77.3% bone marrow blast reduction and desired levels of MCL1 & MYC suppression in peripheral blood with decrease in MCL1 or MYC observed in 97% (66/68) of analyzed patients; complete or partial responses were observed in acute myeloid leukemia and lymphoma patients.

GenFleet received IND approval in 2020 for the GFH009 monotherapy (NCT04588922) to proceed into phase I trial. In 2022, GenFleet and SELLAS Life Sciences Group (Nasdaq: SLS) entered into an exclusive license agreement across all therapeutic and diagnostic uses. GenFleet has started phase Ib/II trial (NCT05934513) of GFH009 treating PTCL (peripheral T-cell lymphomas); conducted by SELLAS, the phase IIa clinical trial of SLS009 (GFH009) with venetoclax and azacitidine is ongoing in the US treating r/r AML patients.  

“This is the first FDA ODD granted to a GenFleet developed product . The support of this ODD will help accelerate later-stage clinical development and commercialization of GFH009 in future. Based on GenFleet's proprietary discovery platform, we will develop more potentially life-saving therapies for unmet medical needs.” stated by Yu Wang, M.D.,Ph.D., Chief Medical Officer of GenFleet. 

Enacted in 1983, the Orphan Drug Act was set up to encourage the development of drugs for rare diseases or conditions affecting small patient populations in US. The benefits provided by ODD include assistance in the drug development process, tax credits for qualified clinical costs, exemptions from certain FDA fees and seven years of marketing exclusivity.

About CDK9 and GFH009

As a family of serine & threonine kinases, the cyclin-dependent kinase (CDK) family plays an important role in cell cycle regulation and transcription; CDK9 activity is inversely correlated with the overall survival rate of patients with multiple tumors. Data from phase I trial and the preclinical research of GFH009 were posted at the 2002 Annual Meeting of the American Society of Hematology. GFH009 monotherapy is well tolerated with preliminary clinical activity in patients with relapsed/ refractory lymphomas and an AML patient observed with complete remission (with no minimal residual disease) lasting for over 8 months. 

According to preclinical research, GFH009 reduces the expression of downstream oncogenes required for rapid cellular division and protein expression through specific, short-lived inhibition of CDK9. With more than 100 times selectivity over other CDK subtypes, this depletion via GFH009 inhibition of CDK9 likely deprives oncogene-addicted cancer cells of crucial survival signals, leading to senescence and death. GFH009 also exhibits strong anti-proliferative activities in multiple human cell lines, effectively inhibits the growth of tumor in various xenograft models and significantly improves survival of tumor bearing animals.