5. Imbruvica

Imbruvica's revenue jumped 16.2% last year as the blood cancer drug leaped from No. 14 to No. 10 on the world's top-20 list by sales.

AbbVie, Johnson & Johnson
2020 sales: $8.43 billion
Diseases: Mantle cell lymphoma, chronic lymphocytic leukemia, Waldenstrom’s macroglobulinemia, marginal zone lymphoma, chronic graft vs. host disease

Competitors came at Imbruvica in 2020 and so did U.S. lawmakers, who wanted to know why a yearly regimen of the drug costs roughly $148,000.

But Imbruvica took the slings and arrows in stride and remained firmly entrenched one of the world’s premier blood cancer drugs. Imbruvica racked up $8.43 billion in sales, an indication that it’s not ready to surrender its dominance of the BTK inhibitor market.

Imbruvica's 2020 sales are split between AbbVie ($5.31 billion) and Johnson & Johnson ($4.13 billion). AbbVie's figure includes $1.009 billion in collaboration revenues, which we removed for this report so it wouldn't be counted twice.  

J&J took an inspired gamble way back in 2011 when it paid less than $1 billion to acquire a 50% stake in the drug. Four years later, the price tag was considerably higher as AbbVie purchased Pharmacyclics and its lone marketed product for $21 billion.

The hefty price was considered outlandish by some analysts. But a year later, Imbruvica helped justify the price, winning a key approval as the first chemotherapy-free treatment for first-line chronic lymphocytic leukemia patients. Since then, the treatment has won six more approvals, the last three coming in combination with other drugs.

RELATED: AbbVie paid a 'lofty,' 'staggering,' 'astronomical' price for Pharmacyclics. But was it too much?       

But there is potential trouble on the way in the form of two serious challengers. 

AstraZeneca’s Calquence, which gained FDA approval in November of 2019, is just as effective in staving off cancer and death and has shown a significantly lower rate of atrial fibrillation, which is linked to stroke and heart failure. 

Calquence is gaining momentum as it continues to win an increasing share of new patients. Last year, Calquence revealed impressive long-term data showing that previously treated mantle cell lymphoma patients went a median 22 months without a worsening of their condition. After three years, more than half were still alive.

RELATED: ASH: AstraZeneca’s Calquence, BeiGene’s Brukinsa turn heads with new data, putting Imbruvica on notice

Imbruvica’s other threat comes from BeiGene’s Brukinsa, which only has approval in the U.S. for mantle cell lymphoma. The med has won a nod in China for relapsed SLL/CLL. 

Late last year, BeiGene showed that against marginal zone lymphoma, Brukinsa could provoke a response in 74% of patients and erase cancer completely in 24% in a year. The corresponding figures for Imbruvika were 48% and 5%, respectively, although the trials didn't test the medicines against each other.

RELATED: AbbVie, already famous for its Humira strategy, forms another ‘patent wall' around Imbruvica: report

To keep its Imbruvica sales coming, AbbVie has built a formidable patent wall around the drug, extending its exclusivity by nine years. If they hold up in court, those additional patents will shield Imbruvica from biosimilar competition and, of course, keep prices high.

The so-called "patent thicket" strategy isn't popular with consumers, insurance companies and the U.S. government. But it is with investors, and it’s all legal, at least for now.

AbbVie has used the strategy with much success as it has extended Humira's run as the world's best-selling drug with the help of an extensive web of patents. In 2018, an I-MAK report on Humira showed that AbbVie had filed 257 patent applications, 130 of which were granted, resulting in a potential 39 years of exclusivity for the drug.

5. Imbruvica