Relay Therapeutics, an oncology drug developer, secured $400 million in its initial public offering Thursday, doubling its expected investment intake.

The Cambridge-headquartered Relay Therapeutics sold 20 million shares at $20 each, beating the price range of $18 to $19 set the day before. Just past noon on Thursday, Relay's stock price climbed 75 percent, reaching $35 per share.

The company's stock market unveiling ranks among the largest biotech industry IPOs, surpassing Allogene Therapeutics' bid of $324 million in 2018 but falling short of Legend Biotech's $424 million this year as well as Moderna's record-breaking $604 million in 2018.

Moreover, the 20 million shares offered represented a spike from 14.7 million shares. Altogether that indicates a solid interest in the Relay Therapeutics initial public bid from institutional investors. Relay's IPO pricing gave it a market valuation of around $1.8 billion.

The SoftBank Vision Fund of Masayoshi Son has invested $300 million in Relay in a funding round of 2018 Series C and holds a 42 percent ownership in the group. An associate of D.E. Shaw & Co. also took part in the auction, earning a combined $400 million. Since its inception Relay has raised a total of $520 million in private rounds.

Relay Therapeutics went public during a time the Renaissance IPO exchange-traded fund has climbed up 49 percent over the past three months, while the S&P 500 has rallied 115 percent.

The clinical-stage therapeutics firm has one vaccine candidate in Phase 1 tests and a second planned later this year for Phase 1 research. The more advanced therapy binds and stabilizes the SHP2 protein to thwart cancer cell development.

Since the pandemic, biotech stocks have been among the most promising ventures on the market. Since the beginning of 2020, the Nasdaq Biotechnology Index has risen 19 percent.

Relay is one of the budding players in the field of precision medicine, employing the latest in computer programming to research how proteins travel and fold in the hopes of making cancer therapies more advanced and successful.

According to documents filed with the SEC, the 122-person business plans to channel up to $120 million from its IPO into the early and mid-stage trials of its lead drug, RLY-1971. The testing of the potential treatment for solid tumors began in February. It is expected to spend upwards of $240 million on Relay's two follow-up vaccines.

Goldman Sachs Group Inc., JPMorgan Chase & Co., Cowen Inc., and Guggenheim Securities also led Relay's bid. The company's stock trades under the symbol RLAY on the Nasdaq Global Exchange.