Investors who have owned stocks in the last year have generally experienced some big gains. In fact, the SPDR S&P 500 (NYSE:SPY) total return over the last 12 months is 47.1%. But there is no question some big-name stocks performed better than others along the way.

Pfizer’s Difficult Road: One company that has been a disappointing investment in the last year has been pharmaceutical giant Pfizer Inc. (NYSE:PFE).

Pfizer investors have likely been extremely disappointed with the performance of the stock in the past year given how much attention the company’s COVID-19 vaccine has gotten. But one of the biggest problems with the vaccine thesis is that it’s unclear how much of a catalyst the vaccine will be for Pfizer beyond 2021. Pfizer recently said COVID-19 vaccine booster shots will “likely” be needed, but it’s difficult to predict how many people will be willing to get them on an annual basis.

Beyond the vaccine thesis, Pfizer’s 6% compound annual revenue growth guidance over the next five years isn’t the type of high-flying growth numbers that investors have been rewarding in the past 12 months. Even after spinning off its generic and off-patent branded drug business, Pfizer is still more of a value stock than a growth stock.

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Still, Pfizer said this week it plans to sell about $15 billion in COVID-19 vaccinations this year at 20% profit margins. Vaccine sales could get a big boost if the virus mutates significantly, reducing the effectiveness of the current batch of vaccines.

At the beginning of 2020, Pfizer shares were trading at around $37. By the beginning of March, the stock was down to $33.59, after news of the coronavirus spreading in China prompted concerns about a U.S. pandemic.

Pfizer bottomed at $27.88 during the pandemic-driven March sell-off. Fortunately for Pfizer investors, the dip did not last long.

By late April, Pfizer shares were back near $40 on vaccine optimism. However, the stock stalled there while Pfizer and other competitors raced to win the vaccine testing and approval race.

Pfizer shares jumped to $41.99 on massive volume in November when the company announced its COVID-19 vaccine was more than 90% effective in late-stage trials.

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Pfizer In 2021, Beyond: The stock ultimately peaked at $43.08 in December 2020 when Pfizer’s vaccine was the first candidate to officially get the green light from the FDA. The stock has since pulled back to $33.36 in late March after investors treated the FDA approval as a sell-the-news event. Pfizer shares have since bounced back to $39.10 on optimism about the near-term vaccine earnings windfall and the potential for additional booster revenue in the future.

Still, Pfizer investors who bought one year ago and held on have generated a lackluster return on their investment. In fact, $1,000 in Pfizer stock bought on April 20, 2020, would be worth about $1,162 today, assuming reinvested dividends.

Looking ahead, analysts are expecting no additional upside for Pfizer in the next 12 months. The average price target among the 19 analysts covering the stock is $39, suggesting 0.4% downside from current levels.