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Happy Tuesday! Pfizer's troubles may finally be coming to a head. 

Former executives of the pharmaceutical giant are backing a push by activist investor Starboard Value to turn around the struggling company, according to recent reports. 

Starboard has a roughly $1 billion stake in the drugmaker and approached former Pfizer CEO Ian Read and ex-CFO Frank D'Amelio, both of whom expressed interest in supporting the activist investor's efforts to shake up the company, CNBC previously reported. As of late Tuesday, Pfizer has a market cap of roughly $165 billion. 

Read and D'Amelio relayed proposals from Starboard to several members of the company's board on Sunday, the Financial Times reported on Monday, citing sources familiar with the conversations. Still, the details of the turnaround plan are scant. 

Read was Pfizer's CEO from 2010 through 2018, while D'Amelio was Pfizer's chief financial officer from 2007 to 2021.

Here's why it matters: Read and D'Amelio's reported involvement is a rare instance of former executives engaging in what could be an activist fight for the future of one of the largest pharmaceutical companies in the world.

Investors have been clamoring for change at Pfizer, whose shares are down more than 30% over the past two years. The company has struggled to recover from the rapid decline of its Covid business, which raked in record-breaking revenue during the peak of the pandemic. 

Pfizer CEO Albert Bourla is facing mounting pressure to improve the company's performance after several commercial missteps over the past two years – including disappointing data on an experimental obesity pill and a slower-than-expected launch of a respiratory syncytial virus vaccine – along with a costly M&A strategy that has yet to yield significant returns. 

Pfizer is betting big on oncology, and particularly its whopping $43 billion acquisition of cancer drug developer Seagen, to regain its footing. But that deal may take years to pay off. Meanwhile, Pfizer last month pulled a key sickle cell disease drug from global markets – the centerpiece of its roughly $5 billion buyout of Global Blood Therapeutics in 2022. 

Starboard's turnaround push raises questions about Bourla's fate at the company. 

"We've sensed investor frustration with CEO Albert Bourla since at least the beginning of 2023," BMO Capital Markets analyst Evan Seigerman wrote in a research note Monday. 

Still, he said, "While placing blame on one person may seem easy, rarely will it result in a quick turn-around."

Other analysts similarly said there may be no quick fix by an activist investor. 

"We await future developments, but we do not see low-hanging fruit to boost shareholder value," Leerink Partners analyst David Risinger wrote in a research note on Monday. 

Risinger said that's because the company faces "revenue growth constraints" over the next five years, driven by patent expirations for top-selling drugs and pressure from competitors. Pfizer has also pursued significant cost-cutting efforts, he added. The company last fall announced that it would cut $4 billion in costs and in May disclosed another multi-year plan to slash roughly $1.5 billion in expenses by 2027. 

Pfizer's debt levels are also relatively high, Risinger noted, with $57.5 billion in debt as of June 30. He said that may only be partially reduced by selling more shares from its assets, such as the consumer health business Haleon. 

We'll continue to follow Starboard's turnaround push, so stay tuned for our coverage.

Feel free to send any tips, suggestions, story ideas and data to Annika at annikakim.constantino@nbcuni.com.

Latest in health-care tech: Hims & Hers to join S&P SmallCap 600 as questions mount around future of its weight loss offering

Shares of Hims & Hers Health, a direct-to-consumer health-care company, closed 10% higher on Monday following the announcement that the stock is being added to the S&P SmallCap 600. 

The S&P Dow Jones Indices said Hims & Hers will replace Vector Group ahead of the opening bell on Oct. 9, according to a release Friday. Japan Tobacco completed its acquisition of Vector Group, which operates tobacco and real estate businesses, on Monday.

Hims & Hers offers treatments for weight loss, sexual health, hair loss and other conditions, and the stock is up nearly 120% year to date as of Monday's close. However, shares of the company tumbled last week after the U.S. Food and Drug Administration announced tirzepatide injections are no longer in shortage. 

Tirzepatide is the active ingredient in Eli Lilly's GLP-1 weight loss drug Zepbound and diabetes drug Mounjaro. Hims & Hers doesn't offer these medications through its platform, but CEO Andrew Dudum told investors in August that the company was looking to introduce access to compounded versions in the near future, as well as the branded versions when supply allowed. 

Compounded medications are custom-made alternatives to the brand drugs, and they can be produced when brand-name treatments are in shortage. Hims & Hers has been offering customers compounded versions of semaglutide, the active ingredient in Novo Nordisk's GLP-1s called Wegovy and Ozempic.

"We don't offer access to tirzepatide at this time," a Hims & Hers spokesperson told CNBC in a statement Monday. "Whenever we bring a treatment to our platform, our first consideration is how accessible it will be for the large majority of customers and accessible means consistently available at a reasonable price."

Hims & Hers is one of several digital health companies selling compounded GLP-1 medications as a cheaper alternative for consumers while demand for the weight loss and diabetes drugs spikes. But they're not a foolproof way to carve out a piece of the anti-obesity drug market, which some analysts estimate could generate $100 billion in annual revenue by 2030.

Both Zepbound and Mounjaro are under patent protection in the U.S., and Eli Lilly does not supply the active ingredient of those two drugs to outside groups. The FDA warned last week that outsourcing facilities are generally restricted from compounding copies of an approved drug unless it's on the shortage list. 

"When a drug shortage is resolved, FDA generally considers the drug to be commercially available," the agency said on its website. "Certain amounts are permissible under the law as long as the compounding is not done 'regularly or in inordinate amounts.'"

Though Hims & Hers does not offer compounded tirzepatide, the FDA's announcement was enough to spook investors. Shares of Hims & Hers closed down nearly 10% on Thursday.  

Analysts at Citi said that Hims & Hers will not be directly impacted by the tirzepatide news, but it does limit the company's total addressable market. It also suggests that shortages could resolve faster than anticipated, they added.

"HIMS has maintained that it will be able to continue to compound GLP-1s after shortages abate by changing the form factor/formulation/dosage for the clinical benefit of an individual," the analysts wrote in a Thursday note. "In our view, this sets HIMS up for a legal battle in the coming months." 

Feel free to send any tips, suggestions, story ideas and data to Ashley at ashley.capoot@nbcuni.com.