April 18 Quick Takes: Radiopharmaceuticals play Ariceum tops off series A

New investors Andera Partners and Earlybird Venture Capital joined existing investor Pureos Bioventures in a €22.8 million ($25.1 million) series A extension for Ariceum Therapeutics GmbH, bringing the total raised in the round to €47.8 million. Ariceum’s lead product, 177Lu-satoreotide tetraxetan, is an antagonist of SSTR2 that Ariceum obtained from Ipsen Group (Euronext:IPN; Pink:IPSEY) and is evaluating in the clinic to diagnose and treat neuroendocrine and other tumors expressing SSTR2. Olivier Litzka from Andera Partners and Christoph Massner from Earlybird will join Ariceum’s board.

The challenges of inhibiting PI3K isoforms continue with initial data for mutant RLY-2608 from Relay Therapeutics Inc. (NASDAQ:RLAY) pointing to limited clinical efficacy for the allosteric PI3Kα mutant inhibitor. In the ReDiscover dose escalation study, RLY-2608 led to one partial response in an HR-positive, HER2-negative breast cancer patient who had progressed on 12 prior lines of treatment, though the therapy reached 80% target exposure at doses of 400 mg twice daily or above. Toxicity has been a persistent problem for PI3K inhibitors, but the company reported no Grade 3 or higher hyperglycemia, rash or diarrhea at the doses tested in the 42 patients treated. Relay shares fell $6.60 (36%) to $11.62 on Tuesday...