In the latest trading session, GlaxoSmithKline (GSK) closed at $45.04, marking a +0.45% move from the previous day. The stock lagged the S&P 500's daily gain of 0.92%. At the same time, the Dow added 0.51%, and the tech-heavy Nasdaq gained 0.54%.Prior to today's trading, shares of the drug developer had gained 4.01% over the past month. This has outpaced the Medical sector's loss of 2.74% and the S&P 500's loss of 0.85% in that time.Wall Street will be looking for positivity from GlaxoSmithKline as it approaches its next earnings report date. In that report, analysts expect GlaxoSmithKline to post earnings of $0.67 per share. This would mark year-over-year growth of 8.06%. Meanwhile, the Zacks Consensus Estimate for revenue is projecting net sales of $12.8 billion, up 10.89% from the year-ago period.Investors should also note any recent changes to analyst estimates for GlaxoSmithKline. These revisions help to show the ever-changing nature of near-term business trends. As such, positive estimate revisions reflect analyst optimism about the company's business and profitability.Research indicates that these estimate revisions are directly correlated with near-term share price momentum. Investors can capitalize on this by using the Zacks Rank. This model considers these estimate changes and provides a simple, actionable rating system.The Zacks Rank system, which ranges from #1 (Strong Buy) to #5 (Strong Sell), has an impressive outside-audited track record of outperformance, with #1 stocks generating an average annual return of +25% since 1988. Within the past 30 days, our consensus EPS projection has moved 0.31% higher. GlaxoSmithKline is holding a Zacks Rank of #3 (Hold) right now.Investors should also note GlaxoSmithKline's current valuation metrics, including its Forward P/E ratio of 13.76. This represents a premium compared to its industry's average Forward P/E of 12.87.It is also worth noting that GSK currently has a PEG ratio of 2.38. The PEG ratio is similar to the widely-used P/E ratio, but this metric also takes the company's expected earnings growth rate into account. Large Cap Pharmaceuticals stocks are, on average, holding a PEG ratio of 2.02 based on yesterday's closing prices.The Large Cap Pharmaceuticals industry is part of the Medical sector. This industry currently has a Zacks Industry Rank of 182, which puts it in the bottom 29% of all 250+ industries.The Zacks Industry Rank gauges the strength of our individual industry groups by measuring the average Zacks Rank of the individual stocks within the groups. Our research shows that the top 50% rated industries outperform the bottom half by a factor of 2 to 1.To follow GSK in the coming trading sessions, be sure to utilize Zacks.com. Zacks’ Top Picks to Cash in on Artificial Intelligence This world-changing technology is projected to generate $100S of billions by 2025. From self-driving cars to consumer data analysis, people are relying on machines more than we ever have before. Now is the time to capitalize on the 4th Industrial Revolution. Zacks’ urgent special report reveals 6 AI picks investors need to know about today.See 6 Artificial Intelligence Stocks With Extreme Upside Potential>>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 GlaxoSmithKline plc (GSK): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research