Sept 6 (Reuters) - Zenas BioPharma, which is developing

immunology-based therapies, said on Friday it is targeting a

valuation of as much as $689.7 million in its initial public

offering in the United States.

The company, backed by drugmaker Bristol-Myers Squibb ( BMY )

, is looking to raise as much as $211.7 million by

offering 11.76 million shares priced between $16 and $18 each.

The proposed offering comes months after Zenas raised $200

million in a funding round led by venture capital firm SR One.

The Waltham, Massachusetts-based company is developing its

lead product candidate, obexelimab, for the treatment of several

immunology and inflammation diseases including multiple

sclerosis and systemic lupus erythematosus (SLE).

SLE is a chronic disease where the body's immune system

attacks its own tissues and multiple sclerosis is a chronic

neurological disorder.

To date, Zenas does not have any products approved for

commercial sale and is yet to generate any revenue.

The listing comes as the U.S. IPO market returns back from

its traditional summer lull.

The company's backers also include investment firms

Fairmount Funds and Norwest Venture Partners.

Zenas will list on the Nasdaq Global Select Market under the

ticker symbol "ZBIO".

The offering is being underwritten by Morgan Stanley,

Jefferies, Citigroup Global Markets and Guggenheim Securities.

(Reporting by Arasu Kannagi Basil in Bengaluru)