Is Jazz Pharmaceuticals Plc overvalued or undervalued?

As of 5 August 2025, Jazz Pharmaceuticals Plc has moved from an attractive to a risky valuation grade. The company appears to be overvalued, as indicated by its P/E ratio of 14, which is lower than the peer average of approximately 16.11, and a PEG ratio of 0.68, suggesting potential growth at a reasonable price compared to its peers. Additionally, the EV to EBITDA ratio stands at 7.69, which is more favorable than some peers like Neurocrine Biosciences, Inc. with an EV to EBITDA of 25.28, but still reflects a concern given the overall risk profile.
In terms of peer comparison, Jazz Pharmaceuticals is positioned against companies like Viatris, Inc., which has a P/E ratio of 44.86, and Neurocrine Biosciences, Inc., which has a significantly higher P/E of 37.08. While Jazz has shown a 1-year stock return of 19.74%, outperforming the S&P 500's 17.14%, its longer-term performance has been underwhelming, with a 3-year return of -11.05% compared to the S&P 500's 70.41%. This mixed performance further supports the view that the stock is currently overvalued.