By Colin Kellaher

Fusion Pharmaceuticals Inc. on Monday said it expects to sell 8.35 million shares at $14 to $16 apiece in its initial public offering.

At the $15 midpoint of that range, the Hamilton, Ontario, clinical-stage oncology company said it expects net proceeds of about $111.9 million, or roughly $129.4 million if the underwriters exercise an option to buy an additional 1.25 million shares.

Fusion said it would use part of the proceeds for the development of FPI-1434, its lead product candidate, as monotherapy and in combination therapies.

In a filing with the Securities and Exchange Commission, Fusion said it would have about 38.8 million shares outstanding after the IPO, assuming exercise of the overallotment option, for a valuation of about $581.5 million at the $15-a-share midpoint.

Fusion's major shareholders include Varian Medical Systems Inc., which owns an 11.3% stake, and Johnson & Johnson, which holds a roughly 10.4% interest.

Fusion said it has applied to list its shares on the Nasdaq Global Market under the symbol FUSN.

Write to Colin Kellaher at colin.kellaher@wsj.com