Maryland lawmakers have penned a letter to Pfizer asking the New York-based pharmaceutical giant to ensure that it will not shed jobs at Gaithersburg-based MedImmune should it succeed in acquiring parent company AstraZeneca.

Pfizer has offered as much as $106 billion to acquire United Kingdom-based AstraZeneca in a deal that could rank among the largest ever for the pharmaceutical industry. So far, the companies have not agreed on a purchase price.

Still, the prospect of a deal has Maryland representatives touting the merits of maintaining a large presence in Montgomery County, where MedImmune has long been located. AstraZeneca bought the company for $15.6 billion in 2007.

“The MedImmune research facility in Maryland has an international reputation for world-class expertise and is located in the heart of our nation’s biotech corridor near the National Institutes of Health. If a deal moves forward, Pfizer would benefit greatly from maintaining their Maryland facilities and workforce,” lawmakers state in the letter.

The letter is signed by Sens. Barbara A. Mikulski and Ben Cardin, as well as congressional Reps. C.A. Dutch Ruppersberger, Chris Van Hollen, John Sarbanes and John K. Delaney, all Maryland Democrats.

British lawmakers have raised similar concerns that an acquisition could mean the loss of jobs in the United Kingdom. Pfizer sought to assuage those concerns last week by pledging to keep jobs there should a deal go through.

But Delaney said in an interview that those efforts have only heightened concerns at home.

“You worry that may put more pressure on decisions they make in the U.S.,” he said.

In their letter, lawmakers asked Pfizer chief executive Ian Read for similar guarantees.

“As you evaluate your next steps, we ask you to extend similar assurances to those you gave in the UK to the research and development workforce in Maryland. AstraZeneca and its MedImmune subsidiary have strong presences in the state, and their workforces are highly skilled and extremely effective.”

Read responded to similar concerns in a May 12 letter to Maryland Gov. Martin G. O’Malley, saying it would be “premature to speculate” on what might happen to MedImmune’s jobs and facilities because “we are in the very early stages of our proposal and are not in direct discussions.”

“I recognize that Maryland has made a significant investment to the biopharmaceutical industry and I understand your interest in the specific impact to your state,” Read wrote. “Pfizer values your investment and the important science being conducted there. MedImmune, a key biologics arm of AstraZeneca’s [research and development] platform, demonstates incredible value to patients by developing innovation driven biopharmaceuticals. Leveraging biological advances to develop small and large molecule medicines, MedImmune’s modality independent approach to research and development would be a good complement to Pfizer’s research efforts in a potential combination with AstraZeneca, and could create and enhanced research portfolio in key areas such as Oncology, Immunology and Cardiovascular Disease.”

Read the full text of the congressional letter below:

Dear Mr. Read,

We are writing to express our concern about potential job losses in our state that could flow from Pfizer’s potential takeover of AstraZeneca. We understand you are likely to submit another offer before a May 26 deadline. As you review your options moving forward, we request you give serious consideration to the US jobs at stake in this possible acquisition. Particularly, AstraZeneca currently employs over 3,000 people in Maryland.

It has been widely reported that if a deal moves forward, Pfizer has committed to keeping at least 20 percent of the combined company’s research and development workforce in the UK for at least five years, as well as retaining substantial manufacturing facilities at AstraZeneca’s site south of Manchester. Given the distribution of AstraZeneca’s current workforce, we worry that jobs in the United States would be eliminated in the takeover.

As you evaluate your next steps, we ask you to extend similar assurances to those you gave in the UK to the research and development workforce in Maryland. AstraZeneca and its MedImmune subsidiary have strong presences in the state, and their workforces are highly skilled and extremely effective. In addition, the MedImmune research facility in Maryland has an international reputation for world-class expertise and is located in the heart of our nation’s biotech corridor near the National Institutes of Health. If a deal moves forward, Pfizer would benefit greatly from maintaining their Maryland facilities and workforce.

Thank you for your attention in the matter, and we look forward to your response.

Sincerely,

Senator Barbara A. Mikulski

Senator Benjamin L. Cardin

C.A. Dutch Ruppersberger, Member of Congress

Chris Van Hollen, Member of Congress

John Sarbanes, Member of Congress

John K. Delaney, Member of Congress

Follow reporter Steven Overly on Twitter: @StevenOverly