Stocks making the biggest moves premarket: Biogen, Viacom, Boeing, Deutsche Bank & more

Check out the companies making headlines before the bell:

Biogen — The drugmaker announced a new $5 billion share repurchase program, in addition to the $1.7 billion remaining under a prior authorization. That follows the stock's plunge last week, following the decision to end a late stage study of an Alzheimer's treatment that did not produce the desired results.

Viacom — Viacom and AT&T reached a new agreement to keep Viacom channels on AT&T platforms like DirecTV and U-Verse. The two sides had agreed to continue contract negotiations past a Friday night deadline.

Boeing — Boeing hosted teams from three U.S. airlines over the weekend to review a software upgrade for the grounded 737 MAX fleet, and is planning a Wednesday information session for pilots, technical leaders, and regulators as it moves to return the jet to service after two fatal crashes over the past few months.

Fiat Chrysler — Fiat Chrysler rebuffed a merger approach from Peugeot parent PSA Group earlier this year, according to The Wall Street Journal. The FT reports, however, that the company's chairman, John Elkann, is making a renewed push to team up with another automaker.

Deutsche Bank — Deutsche Bank and German rival Commerzbank have hit a snag in their merger talks, according to The Wall Street Journal, with the fate of Deutsche Bank's U.S. operations among the contentious issues.

Thermo Fisher Scientific — Thermo Fisher is buying privately held Brammer Bio for $1.7 billion to expand the lab equipment maker's presence in the gene therapy field.

Winnebago — The recreational vehicle maker earned an adjusted 68 cents per share for its fiscal second quarter, 10 cents a share above estimates. Revenue was short of Wall Street forecasts, however, and Winnebago said market conditions have been challenging over the past six months. The company said it is optimistic that conditions are improving.

Eli Lilly — Lilly said the price it has been paid for its popular Humalog insulin dropped to an average of $135 per month per patient in 2018, down from $147 in 2014. The information was released amid increased scrutiny for Lilly and other pharmaceutical companies over prescription drug prices.

Apple — Apple is set to unveil new video and news services today at an event at its California headquarters.

Allergan — Allergan said it would split its chairman and chief executive roles, but not until its next leadership change. Activist investor Appaloosa has been pushing for an immediate split of the two roles.

Avaya — Avaya is considering a buyout offer from a private-equity firm, whose identity could not be learned. The offer values the telecom equipment and software maker at more than $5 billion or more than $20 per share.

Nu Skin Enterprises — Nu Skin was downgraded to "sell" from "hold" at Stifel Nicolaus, which expressed concerns about regulatory risk in the China market for the health products maker.

Tesla — Registration data suggests that Tesla sales may have slumped, according to The New York Times. Separately, RBC Capital lowered its price target on the stock to $210 from $245 while maintaining an "underperform" rating, citing sagging demand.

CORRECTION: This article has been updated to show that Winnebago earned an adjusted 68 cents per share for its fiscal second quarter, 10 cents a share above estimates.