With the S&P 500 down more than 25% this year, the stock market has not been a very attractive place for investors to be lately. However, now is the time when you can find exceptional stocks at a bargain -- an opportunity that will not be available in a bull market.

If investors are still hesitant to put more money into the market, there are some attractive growth stocks available for as little as $20. Investors do not need a bucket full of money to buy shares of healthcare specialist Exelixis (EXEL -1.51%) and rising cannabis company Tilray Brands (TLRY -6.60%).

Let's take a look at why these are the smartest stocks to buy and hold now.

Seedlings on six rising stacks of coins.

Image source: Getty Images.

1. Exelixis

Oncology is a competitive field, but it is also one that is rapidly growing. This market is projected to grow at a compound annual rate of 8%, reaching $536 billion by 2029. Exelixis' attempt to address tough-to-treat cancers using gene treatments has put the business on investors' radar. Cabometyx (cabozantinib), its crown jewel, is used to treat advanced renal cell carcinoma (RCC), a kind of kidney cancer, and several other types of cancer.

In 2021, this medicine alone generated $1 billion in sales. Cabometyx has contributed to Exelixis' survival in the industry up until now. It will continue to do so because it is undergoing many other clinical trials testing it as a combination treatment. 

Cabometyx contributed $339 million in sales in Q2, accounting for the lion's share of overall revenue. Cometriq, which is used to treat thyroid cancer, added $7.9 million. Total revenue of $419 million was up from $385 million in Q2 2021. However, adjusted net income dropped from $118 million in the prior-year quarter to $90 million.

Despite the success of its star drug, investors worry Exelixis is highly reliant on one product. Fortunately, the company is aware of the issue and is focused on a "growing pipeline of clinic compounds, including XL092, XB002, XL102, and XL114." It expects positive outcomes from these upcoming drugs in the second half of the year. Revenue for the full year is projected to be in the range of $1.5 billion to $1.6 billion.

The drugmaker ended the quarter with $2 billion in cash, cash equivalents, restricted cash equivalents, and investments -- enough to fuel its pipeline progress. Exelixis already has one top drug and an attractive pipeline in the works. This biotech company has a lot of room to grow. Down 36% from its all-time high, this growth stock is available at a discount now.

2. Tilray

President Joe Biden's Oct. 6 announcement, pardoning federal marijuana possession convictions, sparked curiosity among pot investors. He also called for a review to be initiated to reclassify marijuana from the Schedule I drug list. Though these initiatives might not benefit cannabis companies directly, they do signal some progress toward positive marijuana reforms.

Some popular companies in this sector, such as Aurora Cannabis and Canopy Growth, are struggling to be EBITDA positive. Meanwhile, Canada-based Tilray Brands has been consistently profitable from an operational standpoint. Its fiscal Q1 2023 marked its 14th consecutive quarter of positive EBITDA, which came in at $13 million.

However, demand and supply mismatches caused revenue to dip by 9% from the year-ago period to $153 million. Tilray is confident in hitting its target of $70 to $80 million in adjusted EBITDA and being free-cash-flow positive this fiscal year. It also aims to bring in $4 billion in yearly revenue by the end of fiscal 2024.

Much of this aggressive target is dependent on federal U.S. cannabis legalization, without which Canadian companies cannot sell their products in the U.S. But legalization could be a long shot. Tilray's focus instead should be on the Canadian and European markets, where it is well-positioned compared to its peers.

It is estimated that the cannabis industry will be worth $149 billion by 2031. But this nascent industry is not for the faint of heart. Investors who can bear these risks may be interested in Tilray, which is trading as low as $3. The stock is down 60% this year, making it the right time to consider it now.