The CSL Ltd (ASX: CSL) share price is up 1.3% in afternoon trade today.

Shares in the S&P/ASX 200 Index (ASX: XJO) biotech stock closed yesterday trading for $280.08. At time of writing on Wednesday, shares are swapping hands for $283.60 apiece.

As you can see on the chart below, that leaves the biotech stock down around 6% since this time last year.

As you can also see, CSL enjoyed a big rebound at the end of October, with shares up more than 22% since 31 October.

But for the CSL share price to hit $500 it would need to gain another 79% from current levels.

Is that achievable in just three years?

According to the analysts at Macquarie, it most certainly is.

As a bit of background, CSL has three operating arms: CSL Behring (the company's blood plasma segment), CSL Vifor, and its Seqirus businesses.

The company acquired CSL Vifor, a global leader in iron deficiency therapies, in 2022 for US$11.7 billion.

While Vifor has been struggling to achieve growth since that acquisition, it's the Behring division that Macquarie believes could help propel the CSL share price to new heights.

As The Australian Financial Review reports, Macquarie's analysts believe the biotech giant is trading significantly below its 10-year average price-to-earnings (P/E) ratio. Macquarie expects CSL to trade back at historic P/E ratios amid annual earnings growth of some 15%.

That's based expectations that CSL Behring will make up 90% of that earnings growth over the next five years.

As for the CSL share price hitting $500 in three years, the analysts said, "We see this as both attractive and achievable."

Indeed, when CSL reported its half-year results on 13 February, CEO Paul McKenzie said:

For FY 2024, I am pleased to reaffirm our previous guidance. CSL's underlying profit, NPATA is expected to be in the range of approximately $2.9 billion to $3.0 billion at constant currency, representing growth over FY23 of approximately 13% to 17%.

Scott Olsson, a portfolio manager at Firetrail Investments' Australian high conviction fund, which owns CSL stock, is also bullish on the outlook for the CSL share price, citing a pullback in the high costs encountered during the pandemic alongside an improved outlook for the company's plasma collections.

According to Olsson (quoted by the AFR):

We think CSL presents a buying opportunity now because the market is more sceptical on management than it has been in the past, and the Vifor acquisition is turning out to not be a great buy so far, but that's a very small part of the business. I think the market is quite distracted on a few things."

Atop Macquarie and Firetrail, a number of other investment experts are bullish on the outlook for the CSL share price.

As the Motley Fool reported yesterday, Morgans has an 'add' rating and $315.40 price target on the ASX 200 biotech stock's shares.

The analysts at UBS recently gave CSL the equivalent of a 'buy' rating, with a $330.00 price target.

Now, these are 12-month price targets, mind you, while Macquarie's $500 a share forecast for CSL is a three-year prediction.