MiNA Therapeutics has raised £23 million ($30 million) to advance a pipeline of small activating RNAs (saRNAs) aimed at previously undruggable targets. The series A round will enable MiNA to move lead drug MTL-CEBPA into a phase 2 liver cancer trial in combination with Bayer’s Nexavar.
London-based MiNA has made a name for itself in recent years as a developer of saRNAs designed to drive the upregulation of target proteins. The drugs are structurally similar to siRNAs but work in a different way once inside a cell. Upon entering the nucleus, saRNAs recruit endogenous transcription complexes, leading to the production of new mRNA and, by extension, the targeted protein.
Boehringer Ingelheim teamed up with MiNA to apply the approach to nonalcoholic steatohepatitis and other fibrotic diseases in 2017. Earlier this year, AstraZeneca began working with MiNA to assess the application of saRNAs to metabolic diseases.
MiNA has advanced its internal pipeline in parallel to those partnered programs, culminating in the delivery of phase 1b data on the use of MTL-CEBPA in combination with Nexavar earlier this year. The readout encouraged MiNA to plan a phase 2 study, creating a need for cash to fund the work.
Israeli VC aMoon has met MiNA’s need for money, leading a £23 million series A with the support of existing investors in the biotech. In aMoon, MiNA has gained the support of a VC that has supported companies including Adicet Bio, a Regeneron-partnered gamma delta T-cell player that has received funding from groups including the investment wings of Novartis and Johnson & Johnson.
The money will fund a phase 2 designed to validate MTL-CEBPA, a drug intended to increase levels of the C/EBP-⍺ master regulator of myeloid cell differentiation. Increasing levels of the protein could reduce the myeloid cell immunosuppression, thereby making other cancer drugs more potent.
The most recent evidence (PDF) to support the hypothesis comes from a phase 1b study of 36 patients with advanced hepatocellular carcinoma (HCC). Among 16 viral HCC patients naïve to prior tyrosine kinase inhibitor treatment, there were two complete responses and two partial responses. MiNA compared the data favorably to the results on Nexavar as a monotherapy, which achieved (PDF) a 1% rate of complete responses in a head-to-head comparison with Opdivo run by Bristol Myers Squibb.
MiNA is also evaluating whether MTL-CEBPA enhances the efficacy of checkpoint inhibitors such as Opdivo. A phase 1/1b trial in advanced solid tumor patients is giving the drug in combination with Merck’s Keytruda. The series A will support that early-phase study and discovery-stage work on new saRNAs against metabolic, immuno-oncology and genetic targets.
MTL-CEBPA and the earlier-stage assets made it this far with the financial backing of Sosei. The Japanese company took a 26% stake in MiNA in return for $35 million in 2017, securing itself an option to buy the British biotech in the process. Sosei let that option lapse the following year due to “strategic prioritization.”