We expect Arena Pharmaceuticals, Inc. ARNA to beat estimates when it reports second-quarter 2017 earnings on Aug 7, after the market closes.Year to date, Arena’s shares have significantly soared 69.7% compared with the industry’s 9% increase.Arena’s earnings performance is a mixed bag. The company surpassed expectations in two of the last four quarters, posted in-line results in one and missed estimates in another. Overall, the company delivered an average positive surprise of 73.46% in the trailing four quarters.Arena Pharmaceuticals, Inc. Price and EPS Surprise Arena Pharmaceuticals, Inc. Price and EPS Surprise | Arena Pharmaceuticals, Inc. QuoteLast quarter, the company missed expectations with a negative earnings surprise of 12.50%. Let’s see how things are shaping up for this announcement.Factors at PlayThe only approved product in Arena’s portfolio is obesity treatment drug, Belviq, which has delivered an unimpressive performance so far. We note that ramping up sales in the U.S. anti-obesity market is challenging due to several factors, including the tendency of health care providers to treat the symptoms of obesity instead of the disease itself, lesser focus on certain patient types for the treatment and historically, low third-party insurance coverage. However, the company’s partnership agreements and efforts to improve Belviq’s performance are likely to show some positive results in the second quarter.Arena has struck partnership agreements with quite a few companies for Belviq. Earlier this year, the company announced that it has amended the marketing and supply agreement with Eisai Co., Ltd. for Belviq. Eisai will gain global commercialization rights for Belviq, including the territories retained by Arena under the companies’ previous agreement, with control development and commercialization decisions globally. It will also take care of all expenses related to the development of Belviq. Going forward, Arena will be entitled to receive royalty payments on sales of Belviq from Eisai.Other collaborations include deals with Ildong for South Korea, CY Biotech for Taiwan and Teva Pharmaceutical TEVA for Israel.Arena has few candidates in its pipeline on which, we expect an update in the second-quarter conference call. Last month, the company announced that a phase II study evaluating its key pipeline candidate, ralinepag, in pulmonary arterial hypertension (PAH), met its primary endpoint. This positive data from the trial paves way for an expedited initiation of a phase III program on the candidate.Other candidates include etrasimod (phase II for ulcerative colitis with data expected in the fourth quarter of 2017) and APD371 (phase II study for treatment of pain associated with Crohn’s disease). Etrasimod has the potential to be developed for additional indications beyond inflammatory bowel disease.During the upcoming release, investors are expected to focus on the company’s progress with its pipeline and the impact of its streamlining efforts.What Our Model IndicatesOur proven model shows that Arena is likely to beat estimates this quarterbecause it has the right combination of two key ingredients. For astock needs to have both a positive Earnings ESP and a Zacks Rank #1 (Strong Buy), 2 (Buy) or 3 (Hold) for this to happen.Zacks ESP: Earnings ESP, which represents the difference between the Most Accurate estimate of a loss of 64 cents and the Zacks Consensus Estimate of a loss of 68 cents, stands at +5.88%. This is a leading indicator of an earnings beat likely positive earnings surprise. You can uncover the best stocks to buy or sell before they’re reported with our Earnings ESP Filter.Zacks Rank: Arena currently carries a Zacks Rank #2, which increases the predictive power of ESP and its positive ESP also make us confident about an earnings surprise. We caution against the Sell-rated stocks (#4 or 5) going into the earnings announcement, especially when the company is seeing negative estimate revisions.Other Stocks That Warrant a LookSyndax Pharmaceuticals, Inc. SNDX is expected to release results on Aug 8 with an Earnings ESP of +9.88% and a Zacks Rank #2. You can see the complete list of today’s Zacks #1 Rank stocks here.Puma Biotechnology, Inc. PBYI is expected to release results on Aug 8. The company has an Earnings ESP of +3.33% and a Zacks Rank #3.More Stock News: Tech Opportunity Worth $386 Billion in 2017 From driverless cars to artificial intelligence, we've seen an unsurpassed growth of high-tech products in recent months. Yesterday's science-fiction is becoming today's reality. Despite all the innovation, there is a single component no tech company can survive without. Demand for this critical device will reach $387 billion this year alone, and it's likely to grow even faster in the future.Zacks has released a brand-new Special Report to help you take advantage of this exciting investment opportunity. Most importantly, it reveals 4 stocks with massive profit potential. See these stocks now>>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Arena Pharmaceuticals, Inc. (ARNA): Free Stock Analysis Report Syndax Pharmaceuticals, Inc. (SNDX): Free Stock Analysis Report Puma Biotechnology Inc (PBYI): Free Stock Analysis Report Teva Pharmaceutical Industries Limited (TEVA): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research