Circle Pharma announced Wednesday September 16, 2026 an oversubscribed $92.5 million Series E financing led by The Column Group with participation from Nextech Invest, RA Capital Management, Euclidean Capital, and Eli Lilly and Company. Founded in 2012, the South San Francisco biotech develops orally bioavailable macrocyclic peptides against cancer-driving intracellular protein-protein interactions historically considered undruggable by conventional small molecules. Lead asset CID-165 is an oral macrocyclic peptide cyclin D1 RxL inhibitor designed to block the interaction between cyclin D1 and its downstream substrates in ER-positive breast cancer. Proceeds advance CID-165 into early clinical development plus expansion of the broader Circle discovery pipeline. Lilly's investor participation adds to a growing Lilly obesity-and-oncology-adjacent equity portfolio that already includes Moonwalk Biosciences (adipose RNAi, $70M Series B September 8), Superluminal Medicines (MC4R agonist, $60M Series B September 3), and Verve Therapeutics (base editing, acquired July 2025). The macrocyclic peptide category has attracted substantial VC and pharma investment throughout 2026, with Syneron Bio, Parabilis Medicines (formerly FogPharma), Bicycle Therapeutics, Unnatural Products, and Circle Pharma all closing major funding rounds or strategic collaborations.
Solstice Oncology, a Boston-based clinical-stage immuno-oncology company founded February 2026, announced Wednesday September 9, 2026 its formal launch and closing of an oversubscribed $225 million Series A financing to advance porustobart, a second-generation Fc-enhanced CTLA-4 monoclonal antibody licensed from Harbour BioMed. The Series A was led by RA Capital Management with participation from Canaan Partners, Forbion, and other investors. Porustobart is heading into a Phase 2 neoadjuvant trial combining with pembrolizumab (Merck's Keytruda) for microsatellite-stable clinical stage II-III colon cancer, targeting enrollment opening Q4 2026, plus a second undisclosed indication. Fc-enhancement is designed to improve the antibody's ability to deplete regulatory T-cells and enhance immunogenicity relative to first-generation CTLA-4 inhibitors like ipilimumab (Bristol Myers Squibb's Yervoy). The financing continues a Q3 2026 immuno-oncology financing wave and demonstrates continued investor appetite for differentiated checkpoint programs despite the maturity of the anti-PD-(L)1 class.
Typewriter Therapeutics announced Thursday September 3, 2026 its emergence from stealth with $56 million in Series A financing co-led by RA Capital Management and AN Venture Partners, with participation from ANRI, Gemseki, and SBI US Gateway Fund. The proceeds will advance the company's target-primed reverse transcription (TPRT) non-viral gene therapy platform toward clinical development, with initial focus on two high-value indications: in-vivo CAR-T and genetic liver diseases. TPRT uses jumping-gene-inspired biology to insert therapeutic DNA at specific target sites without the packaging-size constraints of AAV vectors or the payload delivery constraints of lipid nanoparticles. Typewriter plans to initiate non-human primate studies in late 2026 and establish its first in-vivo CAR-T development candidate over the next 12 months. The financing continues the H2 2026 in-vivo CAR-T financing wave that also delivered Umoja Biopharma's $100 million+ round and Capstan Therapeutics' Series C earlier in the summer.