The shares of PharmaCyte Biotech Inc. PMCB, -7.19% plummeted 55.9% in premarket trading Tuesday, ahead of their debut on the Nasdaq exchange on Tuesday, after the biotechnology company announced the terms and pricing of a relatively large public equity offering. The California-based company, which focuses on developing cellular therapies for cancer and diabetes using its live-cell encapsulation technology, expects its stock to start trading on the Nasdaq under the ticker symbol “PMCB” on Tuesday, after previously trading over the counter. The company also announced details of a previously announced planned equity offering, saying it raised $15 million from the offering of 3.53 million shares of common stock and warrants to buy up to 3.53 million shares of common stock. The stock and warrants to buy a stock was priced at a combined price of $4.25. The stock’s reference price prior to its first trade on the Nasdaq is $7.00, and the company’s market capitalization was $11.14 million, according to FactSet. The stock has already slumped 68.2% over the past three months through Monday, while the iShares Biotechnology ETF IBB, -3.29% has rallied 19.9%, the Nasdaq Composite COMP, -0.27% has advanced 10.9% and the S&P 500 SPX, 0.16% has gained 5.8%.