On Friday, Stamford, Conn.-based SpringWorks filed a preliminary prospectus with the U.S. Securities and Exchange Commission for an IPO. The company is seeking the funds to continue to drive the development of its lead candidates, nirogacestat, a gamma-secretase inhibitor for the treatment of desmoid tumors and PD-0325901 (mirdametinib), a MEK inhibitor for the treatment of neurofibromatosis type 1-associated plexiform neurofibromas. SpringWorks was spun out of Pfizer in 2017 with these two assets in hand, as well as $103 million in Series A financing.
SpringWorks launched a Phase III trial assessing nirogacestat for treatment of desmoid tumors in May, with a primary endpoint of progression-free survival. Desmoid tumors are rare and debilitating soft-tissue tumors that can occur in both children and adults. They can lead to severe morbidities in patients. Last year, SpringWorks received Fast Track designation from the FDA for nirogacestat, for the treatment of adult patients with progressive, unresectable, recurrent or refractory desmoid tumors or deep fibromatosis. In June 2018, the FDA granted Orphan Drug designation for nirogacestat for the treatment of desmoid tumors.
In June, the FDA granted Fast Track designation for PD-0325901 for the treatment of patients with neurofibromatosis type 1-associated inoperable plexiform neurofibromas that are progressing or causing significant morbidity. Last year the asset received Orphan Drug designation. SpringWorks expects to initiate the ReNeu trial, a Phase IIb open-label, single-arm trial with mirdametinib that will enroll both pediatric and adult NF1-PN patients, in the third quarter of 2019.
In its prospectus, SpringWorks said it will use a portion of the funds from the IPO, as well as those currently in its war chest, to expand the company’s portfolio through licensing programs. The company said those programs will have “strong biological rationales and validated mechanisms of action.”
Although the company is only two years old, it’s well-financed with $268 million in hand, according to its prospectus, and has been busy developing its therapeutics, as well as making collaborative deals. In June, SpringWorks and BeiGene teamed up to form MapKure LLC, a new company that will focus on the development of an oncology asset. That asset is BGB-3245, an investigational, oral, selective small-molecule inhibitor of monomer and dimer forms of activating B-RAF mutations including V600 BRAF mutations, non-V600 B-RAF mutations, and RAF fusions. MapKure was formed after the two companies initially got together in the fall of 2018 to develop therapeutics targeting advanced solid tumors that contain RAS mutations, as well as other MAPK aberrations.
More recently, in June, SpringWorks and GlaxoSmithKline formed a clinical trial collaboration to evaluate SpringWorks’ investigational nirogacestat, in combination with GSK’s investigational anti-B-cell maturation antigen antibody-drug conjugate belantamab mafodotin, in patients with relapsed or refractory multiple myeloma. GSK, which supported SpringWorks’ Series B funding round, will sponsor and conduct the adaptive Phase Ib study to evaluate the safety, tolerability and preliminary efficacy of the combination therapy.