X4 Pharma founder Renato Skerlj signs on as its R&D chief

Renato Skerlj takes his post as X4 takes its lead program, a treatment for the primary immunodeficiency disorder WHIM syndrome, into phase 3. (Pixabay)

X4 Pharmaceuticals has a new R&D chief: Renato Skerlj, Ph.D., who founded the company alongside CEO Paula Ragan, Ph.D. and biotech luminary Henri Termeer. Skerlj joins X4 from Lysosomal Therapeutics, where he led drug discovery and preclinical development efforts. 

“Renato’s deep scientific expertise in the research and development of innovative, genetically-targeted treatments, combined with his foundational knowledge of X4 and our novel CXCR4 platform, will be invaluable as we advance our pre-clinical product candidates and further expand our rare disease pipeline,” Ragan said in a statement. 

Skerlj’s appointment follows that of X4 Chief Medical Officer E. Lynne Kelley, M.D. in April. The Cambridge, Massachusetts-based company has been working on its lead asset, mavorixafor, for the rare primary immunodeficiency disorder WHIM syndrome, as well as kidney cancer, the rare blood cancer Waldenstrom macroglobulinemia and severe congenital neutropenia, which makes patients prone to recurrent infections. About one-fifth of people with this type of neutropenia go on to develop blood cancers, according to the NIH. 

RELATED: X4 targets year-end start for phase 3 WHIM trial after determining dose in midphase readout 

In June last year, X4 presented phase 2 data for a combination of mavorixafor, then called X4P-001, and Pfizer’s Inlyta in patients with clear cell renal cell carcinoma, a type of kidney cancer. The treatment shrank tumors in 23% of patients who had been “heavily pretreated.” It will present more data at the annual meeting of the European Society for Medical Oncology later this month. 

X4 is looking for a partner “for future development and potential commercialization for mavorixafor for ccRCC [clear cell renal cell carcinoma] and other potential immuno-oncology indications.” 

It is going full steam ahead on its WHIM program though, kicking off a 28-patient phase 3 study in June. Named for its symptoms—Warts, Hypogammaglobulinemia, Infections and Myelokathexis—WHIM is caused by several different mutations in the chemokine receptor (CXCR4) gene. It has no approved treatment, so care focuses on relieving symptoms and warding off infections. X4’s drug is designed to treat it by targeting the CXCR4 receptor and raising patients’ white blood cell counts. 

The yearlong trial will measure the drug’s ability to boost the level of circulating neutrophils compared to a “clinically meaningful threshold.” It will also study infection rates, wart burden and assessments of immune system function and quality of life.