Updated to reflect Illumina CEO comments and preliminary results from stockholder meeting.

NEW YORK ( TheStreet) -- Swiss pharmaceuticals giant Roche has decided not to extend a $51 a share takeover offer for Illumina ( ILMN - Get Report), signaling that the genomics machinery specialist has fended off a hostile bid.

After making an initial $44.50 per share bid for Illumina in January, Roche boosted its unsolicited offer to $51 a share or roughly $6.8 billion -- an offer Illumina rejected in April. With shareholder proxy services supporting Illumina's defiance, Roche said that the re-election of the company's incumbent directors over a hostile slate of nominees at the company's annual meeting led Roche to let its offer expire rather than raise it.

In deciding not to extend its offer, Roche indicated that it was resistant to a bid increase or extension because of its inability to access Illumina's finances.

"We continue to hold Illumina and its management in very high regard but, with access only to public information about Illumina's business and prospects, we do not believe that a price above Roche's offer for Illumina of $51.00 per share would be in the interest of Roche's shareholders," said Roche CEO Severin Schwan in a statement.

Separately, Illumina said that preliminary voting results from its 2012 annual stockholder meeting signaled that shareholders had rejected four nominees appointed by Roche to the company's board and all of its other proposals. "We thank Illumina stockholders for their support and appreciate their confidence in our ability to execute our strategic plan and create compelling value," said Illumina CEO Jay Flatley of the results.

"We are pleased that Roche has decided not to extend its inadequate offer to acquire Illumina and that we can now return our full focus to growing our business, making the most of the expanding opportunities in our space, and delivering superior results for our customers and stockholders," Flatley added.

On news of the potential bid expiration, which is slated for April 20, Illumina shares dropped over 4.5% to $42.01 -- far below Roche's offer price.

Roche's statement shows that a lack of success in the election of a hostile slate of directors and gaining access Illumina's finances iced its takeover offer. Many analysts had expected that board elections and friendlier negotiations would favor Roche, eventually leading to an offer above $51 a share. Currently, Illumina has enacted a "poison pill" to make it uneconomic for Roche to take a large share stake in the San Diego-based company.

"The important question is whether or not the increased bid is enough to bring Illumina to the negotiating table and allow Roche to learn more about Illumina's closely guarded pipeline," wrote JPMorgan analyst Tycho W. Peterson, in reaction to the company's rejection of Roche's most recent $51 a share offer, earlier in April.

At that time, risk arbitrage analysts at Makor said that the rejection was a first step to an eventual $55 a share takeover, based on the expected election of some Roche-appointed directors to Illumina's board. "These elections will clearly favor the bid from Roche," wrote Makor analysts, who expected a deal completion by mid-June.

During the multi-month sequence of events between Roche and its target, Illumina repeatedly called Roche's bid undervalued, citing fairness opinions from its financial advisors Goldman Sachs ( GS) and Bank of America Merrill Lynch ( BAC).

In April, shareholder proxy service Institutional Shareholder Services agreed with Illumina and its advisors, citing the high potential for the company's new line of genomic machinery products, which may draw in new customers to replace waning government-funded orders that have cut into revenue.

Illumina shares were more than halved last year as the continuation of research grants from large scale government funded efforts like the National Institute of Health came into question. The NIH and similar organizations account for a large portion of Illumina's customers, until it can market new machinery directly to hospitals and patients.

"Given the lack of serious competition in the near future, and the vast potential for sequencing that is already starting to appear, the board should rightfully be concerned about unnecessarily truncating value by selling the company too soon, and at too low a price," I.S.S. wrote on April 6. "At $51, Roche's offer may not be an unreasonable valuation of the company -- but it does not provide shareholders sufficient compensation for the opportunity they would then forgo."

Shares of Illumina and competitor genetic research machinery makers like Life Technologies ( LIFE) have been bolstered by high expectations for new equipment that can bring cancer research directly to patient treatments. Illumina is currently developing machinery to sequence human genomes in a day, bringing down the time horizon from weeks and even months, which should also lower costs.

In bidding for Illumina, Roche would have acquired the leading sequencing specialist, which could also help the company's own drug research and development efforts. Currently Illumina has an over 50% market share in sequencing machinery, as the technology becomes a part of cancer patient treatment, in addition to medical research.

In early April Illumina said it expects that first quarter earnings per-share earnings will meet or exceed analysts' estimates on revenue of about $270 million. Analysts polled by Thomson Reuters expect Illumina to earn 31 cents a share on revenue of $257 million.

Meanwhile, since the hostile bid was launched, analysts said that Illumina could warrant takeover offers as high as $70 a share, based on the expected value of its new genomics products and its strong market position. Many also highlighted Roche's history in raising unsolicited takeover offers substantially.

The proposal by Roche was its third hostile bid in the U.S. pharmaceuticals sector after taking a previous $46.8 billion offer for Genentech and a $3 billion bid for Ventana Medical Systems directly to shareholders. After increasing its Illumina bid, Roche came back to the table with a higher bid in all three instances.

Analysts also pointed to the possibility healthcare giants like Siemens Healthcare ( SIE), Johnson & Johnson ( JNJ), Abbott Laboratories ( ABT) and Becton, Dickinson ( BDX) could compete against Roche's bid; however, no offers emerged.

For more on how deal and trading volumes may impact Wall Street earnings, see why there is a widening investment bank performance gap.

-- Written by Antoine Gara in New York