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NEW YORK (TheStreet) -- Isis Pharmaceuticals (ISIS) has been upgraded by TheStreet Ratings from Sell to Hold with a ratings score of C.  TheStreet Ratings Team has this to say about their recommendation:

"We rate ISIS PHARMACEUTICALS INC (ISIS) a HOLD. The primary factors that have impacted our rating are mixed, some indicating strength, some showing weaknesses, with little evidence to justify the expectation of either a positive or negative performance for this stock relative to most other stocks. The company's strengths can be seen in multiple areas, such as its robust revenue growth, solid stock price performance and compelling growth in net income. However, as a counter to these strengths, we also find weaknesses including generally higher debt management risk and poor profit margins."

Highlights from the analysis by TheStreet Ratings Team goes as follows:

• ISIS's very impressive revenue growth greatly exceeded the industry average of 35.5%. Since the same quarter one year prior, revenues leaped by 100.8%. Growth in the company's revenue appears to have helped boost the earnings per share.
• Powered by its strong earnings growth of 219.04% and other important driving factors, this stock has surged by 28.39% over the past year, outperforming the rise in the S&P 500 Index during the same period. Regarding the stock's future course, our hold rating indicates that we do not recommend additional investment in this stock despite its gains in the past year.
• ISIS PHARMACEUTICALS INC reported significant earnings per share improvement in the most recent quarter compared to the same quarter a year ago. The company has demonstrated a pattern of positive earnings per share growth over the past two years. However, we anticipate underperformance relative to this pattern in the coming year. During the past fiscal year, ISIS PHARMACEUTICALS INC continued to lose money by earning -$0.35 versus -$0.53 in the prior year. For the next year, the market is expecting a contraction of 134.3% in earnings (-$0.82 versus -$0.35).
• The gross profit margin for ISIS PHARMACEUTICALS INC is currently extremely low, coming in at 11.88%. Despite the low profit margin, it has increased significantly from the same period last year. Despite the mixed results of the gross profit margin, ISIS's net profit margin of 36.59% compares favorably to the industry average.
• The debt-to-equity ratio of 1.46 is relatively high when compared with the industry average, suggesting a need for better debt level management.
• You can view the full analysis from the report here: ISIS Ratings Report