Arrowhead Completes Enrollment in Phase 1b Trial of RNAi Drug Candidate CALAA-01

Arrowhead Research Corporation (NASDAQ: ARWR), a targeted therapeutics company, today announced that, through its Calando Pharmaceuticals subsidiary, it has completed enrollment of a phase 1b clinical trial of CALAA-01, its RNAi therapeutic candidate targeting solid tumors. All patients participating in the trial have completed dosing with the exception of one patient who is still receiving treatment and will continue to be monitored. An analysis of final study data is being prepared.

The phase 1b trial is an open-label, dose-escalating study of the safety of intravenously administered CALAA-01 in adults with solid tumors refractory to standard-of-care therapies. CALAA-01 is a combination of the RONDEL™ delivery system and a patented siRNA targeting the M2 subunit of ribonucleotide reductase (RRM2), a clinically validated cancer target.

“We would like to take this opportunity to thank the patients and physicians that made this trial possible,” said Bruce D. Given, M.D., COO and head of R&D for Arrowhead. “Now that the CALAA-01 trial is complete, we will finalize and analyze the data for presentation at a future research meeting.”

About Arrowhead Research Corporation

Arrowhead Research Corporation is a clinical stage targeted therapeutics company with development programs in oncology, obesity, and infectious disease. The company is leveraging its platform technologies to design and develop peptide-drug conjugates (PDCs) that specifically home to cell types of interest while sparing off-target tissues, create targeted drugs based on the gene silencing RNA interference (RNAi) mechanism, and work with partners to create improved versions of traditional small molecule drugs.

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