Chiesi to Buy KalVista Pharmaceuticals for $1.9 Billion

Chiesi Farmaceutici SpA agreed to acquire US-listed KalVista Pharmaceuticals Inc. for about $1.9 billion in its biggest acquisition to date, expanding the Italian company’s rare immunology portfolio.

Closely held Chiesi will start a tender offer to acquire all of KalVista’s shares for $27 per share in cash, after the boards of both companies approved the transaction, according to a statement Wednesday.