A month has gone by since the last earnings report for Pacific Biosciences of California (PACB). Shares have lost about 7.8% in that time frame, underperforming the S&P 500.Will the recent negative trend continue leading up to its next earnings release, or is Pacific Biosciences 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. Pacific Biosciences Incurs Loss in Q1, Revenues Fall Y/YPacific Biosciences incurred first-quarter 2019 adjusted loss of 20 cents per share, wider than the Zacks Consensus Estimate of a loss of 17 cents. The company had incurred a loss of 20 cents in the year-ago quarter.Revenues totaled $16.4 million, which missed the Zacks Consensus Estimate of $22 million and declined 15.2% from the year-ago quarter’s tally.Segmental AnalysisProduct Revenue: At this segment, revenues amounted to $16.4 million, down 17.4% from the prior-year quarter’s tally.Service and Other Revenue: At this segment, revenues came in at $3 million, down 3.6% year over year.Margin AnalysisGross profit in the first quarter of 2019 was $5.1 million, down 29.9% on a year-over-year basis. Gross margin was 31.2% of total revenues, significantly lower than 37.7% of net revenues as reported in the year-ago quarter.Research and Development expenses fell 5.1% to $15.5 million in the quarter. Also, sales, general and administrative expenses rose 32.4% to $19.8 million.Operating expenses totaled $35.3 million, up 12.8% year over year.How Have Estimates Been Moving Since Then?In the past month, investors have witnessed a downward trend in fresh estimates. The consensus estimate has shifted -20.69% due to these changes.VGM ScoresAt this time, Pacific Biosciences has a subpar Growth Score of D, a grade with the same score on the momentum front. Charting a somewhat similar path, the stock was allocated a grade of F on the value side, putting it in the fifth quintile for this investment strategy.Overall, the stock has an aggregate VGM Score of F. 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 this revision indicates a downward shift. Notably, Pacific Biosciences 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 Pacific Biosciences of California, Inc. (PACB): Free Stock Analysis Report To read this article on Zacks.com click here.