By Brett Callwood, Benzinga Staff Writer

Human Genome Sciences (HGSI) is doing whatever it can to avoid a hostile takeover by GlaxoSmithKline (GSK).

The company says it's talking to what it calls "major" pharmaceutical and biotechnology companies to keep GlaxoSmithKline away.

It's a fascinating period of time for HGSI, which claims to have entered into confidentiality agreements with a number of unnamed parties, and is currently providing opportunities to enter into due diligence reviews.

Last week, GSK made an initial $2.6 million tender offer after HGSI turned down a takeover approach.

GSK's offer for HGSI became public knowledge in April, after HGSI shares fell 76% from the company's peak in 2011. It is certainly a generous offer, no matter the noises coming out of HGSI, valuing the company at 11 times estimated 2012 sales.

"Shareholders should have the opportunity to decide for themselves on the merits of the offer," Glaxo said.

Also, the situation is mildly awkward due to the fact that the two companies are currently working together to develop two medicines. So the fact that HGSI is seemingly prepared to do anything to avoid entering into a deal with GSK only serves to exacerbate that awkwardness.

Despite HGSI's board voting unanimously in favor of turning down the GSK's $2.6 billion offer, Glaxo doesn't seem too keen to take no for an answer, stating on May 9 that it would be proceeding with the bid by offering $13 per share in cash directly to shareholders.

Human Genome does seem to want to proceed with a deal, but it will not be bullied, and analysts are predicting that a deal will get done in the region of $15 per share. While the company's attempts to find another buyer may be little more than a healthy game of hardball, GSK will do well to realize that it won't be getting Human Genome on the cheap.

"The rights plan will not prevent any offers or transactions that the board determines to be in the best interest of HGS and its stockholders," the company said Thursday in a separate statement related to the adoption of its short-term rights plan.

In response to GSK's offer, HGSI said in a statement, "The board believes that GSK acted to take advantage of the company's depressed stock price levels."

Both stocks traded lower Thursday.