Sanofi-Aventis has completed a review of the financial books and operations of takeover target Genzyme Corp , but the two sides continue to discuss a final price for a potential deal, according to The Wall Street Journal.

Sanofi did not find any major issues in its review of Genzyme, but it may be looking to adjust its last offer based on what it learned from its examination, the newspaper reported in its electronic edition.

The concern is that they may lower their offer -- pinning it to something they may or may not have found -- and at this point, anything below $74 (a share) would be a disappointment, one trader told Reuters. He declined to be named because he was not authorized to speak to the media.

To gain access to Genzyme's books, Sanofi had agreed to raise its offer from $69 a share to roughly $74 a share, pending due diligence, plus a potential milestone payment based on the success of a multiple sclerosis drug, sources previously told Reuters.

The $74 per share offer would value Genzyme at roughly $19 billion. An additional milestone payment, or so-called contingent value right (CVR), of roughly $5-$6 per share would hinge on the success of experimental drug Lemtrada.

Sanofi and Genzyme continue to hold negotiations and still aim to complete a deal as early as this week, one source familiar with the situation told Reuters. The source declined to be named because the talks were not public.

No announcement is expected on Monday and no final deal has been reached, the source said.

Sanofi's $69 per share tender offer for Genzyme expires on February 15 and the French company has said it may extend the offer for a third time if necessary.

Some investors had hoped a deal would be reached last week, but Sanofi said it was conducting a careful due diligence process. The company said on January 31 that it was beginning two weeks of due diligence on Genzyme, a period that would expire on Monday.

Any review is complicated by the fact that Genzyme is on the mend from a manufacturing crisis that led to shortages of two of its most important drugs.

Sanofi and Genzyme could not be immediately reached for comment.

(Reporting by Jessica Hall; Editing by Vinu Pilakkott)