Shares of Karuna Therapeutics Inc. KRTX, +2.20% more than tripled (up 254%) in active trading, to lift the biopharmaceutical company's market capitalization to well above $1 billion, after a phase 2 trial of its schizophrenia treatment met its primary endpoint. Trading volume ballooned to 6.5 million shares, compared with the full-day average of about 70,000 shares. The company said its KarXT port the treatment of acute psychosis in schizophrenia patients demonstrated a "statistically significant and clinically meaningful" reduction in total positive and negative syndrome scale (PANSS) score compared with a placebo. KarXT was also well tolerated. "With this information, and following our anticipated end-of-Phase 2 meeting with the FDA in the second quarter of 2020, we will work to initiate a Phase 3 clinical trial of KarXT in patients with schizophrenia by the end of 2020," said Chief Medical Officer Stephen Brannan. The stock, which went public on June 28 at an initial-public-offering price of $16, has nearly tripled (up 182%) over the past three months, while the iShares Nasdaq Biotechnology ETF IBB, +2.12% has gained 5.5% and the S&P 500 SPX, +1.59% has rallied 7.9%.