A month has gone by since the last earnings report for Halozyme Therapeutics (HALO). Shares have lost about 7.5% in that time frame, underperforming the S&P 500.Will the recent negative trend continue leading up to its next earnings release, or is Halozyme Therapeutics due for a breakout? Before we dive into how investors and analysts have reacted as of late, let's take a quick look at the most recent earnings report in order to get a better handle on the important catalysts. Halozyme Q1 Earnings & Sales Beat EstimatesHalozyme reported first-quarter 2021 earnings of 34 cents per share (including stock-based compensation expense), which beat the Zacks Consensus Estimate of 28 cents. The company had incurred a loss of 1 cent in the year-ago quarter.Total revenues increased 250.4% year over year to $89.0 million, primarily driven by milestone payments from Bristol-Myers, J&J and higher royalty revenues. The top line also beat the Zacks Consensus Estimate of $85.0 million.Quarterly HighlightsHalozyme’s top line comprises product sales, royalties and revenues under collaborative agreements.Royalty revenues were $36.9 million in the first quarter, up 119.5% from the year-ago quarter, mainly driven by strong sales uptake of J&J’s subcutaneous Darzalex (Darzalex SC). In the quarter, J&J received FDA and Health Canada approval for label expansion of Darzalex Faspro for treating newly diagnosed light chain (AL) amyloidosis in adult patients. The approval should support the future growth of subcutaneous Darzalex and subsequently Halozyme’s royalty revenues.Product sales, solely from the sale of bulk API to collaborators using the ENHANZE platform for drug development, increased 167.2% to $21.8 million in the quarter. The increase was driven by higher bulk API sales to ENHANZE partners, J&J and Roche. Revenues under collaborative agreements were $30.3 million compared with $0.4 million in the prior-year quarter. The significant increase was due to $25 million in milestone payment received from Bristol-Myers (following start of a phase III study on subcutaneous formulation of Opdivo using ENHANZE technology) and $5 million in milestone revenues from J&J (due to approval of Darzalex SC in Japan).Research and development (R&D) expenses declined 11.8% year over year to $9.0 million mainly due to discontinuation of oncology drug development efforts and some development activities related to PEGPH20.Selling, general and administrative (SG&A) expenses were $11.1 million, down 11.9% from the year-ago period.The company repurchased 1.8 million shares of common stock for $76.2 million during the fourth quarter.2021 Guidance MaintainedHalozyme maintained its previously issued guidance for revenues and earnings for 2021. The company expects total revenues in 2021 to be between $375 million and $395 million, indicating year-over-year growth of 40. The company expects revenues from royalties to double year over year on the back of strong uptake of subcutaneous formulation of J&J’s Darzalex and growth in Roche’s Phesgo. Halozyme expects Darzalex SC to be the key driver of its royalty revenue growth in 2021. Product sales are expected to increase 50% to 60% from 2020 levels.It expects earnings to be in the range of $1.55-$1.70 per share (excluding stock-based compensation expense), indicating year-over-year growth of 38.How Have Estimates Been Moving Since Then?In the past month, investors have witnessed a downward trend in estimates review. The consensus estimate has shifted 12.16% due to these changes.VGM ScoresCurrently, Halozyme Therapeutics has a nice Growth Score of B, however its Momentum Score is doing a bit better with an A. However, the stock was allocated a grade of C on the value side, putting it in the middle 20% for this investment strategy.Overall, the stock has an aggregate VGM Score of B. If you aren't focused on one strategy, this score is the one you should be interested in.OutlookEstimates have been broadly trending downward for the stock, and the magnitude of these revisions looks promising. Notably, Halozyme Therapeutics has a Zacks Rank #3 (Hold). We expect an in-line return from the stock in the next few months.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 Halozyme Therapeutics, Inc. (HALO): Free Stock Analysis Report To read this article on Zacks.com click here.