Analyst Update: Tetraphase, Titan International, Wendy's

Analysts are weighing in today on biotech Tetraphase Pharmaceuticals Inc (NASDAQ:TTPH), tire supplier Titan International Inc (NYSE:TWI), and fast food interest Wendy's Co (NASDAQ:WEN). Here's a quick roundup of today's brokerage notes on TTPH, TWI, and WEN.

• TTPH is attempting to make a comeback, last seen up 5.7% at $11.38, after collapsing to a two-year low of $7.20 in late September on the heels of disappointing drug data. Today, Suntrust Robinson raised its rating on Tetraphase Pharmaceuticals Inc to "buy" from "neutral," and increased its price target to $21 from $12. The drugmaker is still down 72.9% year-to-date, but options traders are optimistic that TTPH will be able to recoup some of its losses. The stock's Schaeffer's put/call open interest ratio (SOIR) of 0.36 is lower than all but 1% of readings from the past year -- meaning that traders have rarely been so call-heavy. Still, 18.1% of TTPH's available float is sold short. If the shares continue to recover from their recent lows, a short-covering rally could send them even higher.

• TWI earned a spot on the short-sale restricted list, after falling 12.8% to trade at $4.41 -- just off a new six-year low of $4.33, hit earlier today. The tire and wheel supplier received a downgrade to "sell" from "neutral," along with a price-target cut to $3 from $8, at Goldman Sachs, with the brokerage firm citing an "extended downturn" in the agriculture and mining industries. But the downward motion is nothing new for Titan International Inc, which has been trending lower since May's year-to-date high of $12.50, and recently reported third-quarter results far below expectations on the Street. Only one analyst following the firm gives it anything better than a "hold" rating, and nearly 9% of the stock's float is already sold short. At TWI's average pace of trading -- suggesting there's an unsurprising amount of skepticism priced into the stock already.

• WEN is serving up good news for its shareholders, adding 3.5% so far today to trade at $10.25, after Goldman Sachs upgraded the fast food giant to "buy" and added Wendy's Co to its Conviction Buy list. WEN reported a positive earnings surprise earlier this month -- in part thanks to an increase of pork and chicken offerings on its menu -- and has added nearly 10% year-to-date. Still, only four of 11 brokerage firms give the security a "buy" rating, and options traders have become somewhat wary over the past week. On the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), WEN has a 10-day call/put volume ratio of 4.84 -- right at the 50th percentile of its annual range -- down from a decidedly more bullish reading of 10.38 just last Friday. Today's upgrade could draw more buyers to the table, and there is certainly more room for the shares to rise.

For other stocks in analysts' crosshairs, read Analyst Upgrades: Salesforce.com, Inc., Allergan PLC, and Ctrip.com International, Ltd. and Analyst Downgrades: QUALCOMM, AMAG Pharmaceuticals, Inc., and Keurig Green Mountain Inc