MiNK Therapeutics tumbles after $50 mln stock offering filing

** Shares of MiNK Therapeutics INKT tumble 23.7% premarket to $31 on equity raise plans

** New York City-based firm files up to $50 mln ATM (at-the-market) equity sales program to be handled by B. Riley Secs

** Co expects to use net offering proceeds for working capital, and other general purposes including R&D expenditures, preclinical and clinical development and commercialization of its product candidates, among other purposes

** INKT shares on Fri surged 730% to close at $64.17 after co said its experimental allogeneic cell therapy, agenT-797, showcased complete remission in a patient with advanced testicular cancer, as published in Oncogene

** Mid-stage data expected in upcoming months and study is enrolling patients, co said

** Shares retreated ~37% on Mon, finishing at $40.61

** Co has ~4 mln shares outstanding for $162 mln market cap through Mon, and ~1 mln shares of public float

** 2 brokerages rate INKT "buy" and 1 rates "hold". There are just 2 PTs on the stock: B. Riley ($7) and H.C. Wainwright ($35) - LSEG data