Bashir has spent the past six years working at Citigate Dewe Rogerson, where she was an associate director and had been based in the life sciences and healthcare team since 2017.
She has worked for clients such as Owlstone Medical, Hutchison China Meditech, Calcivis, and Exscientia.
In her new role, Bashir will report to Optimum's founder and managing director, Mary Clark.
Since its launch in 2017, Optimum has grown rapidly and now works with more than 40 companies in pharma, medtech, biotech and healthtech across 13 countries in Europe.
Clark commented: "We are proud to work with some of the most innovative and successful companies in the life sciences and healthcare sector, supporting our clients through fundraisings and major milestones."
She added that the agency has "grown significantly in the past year" and that "Shabnam's appointment will enable us to build on this success and support our integrated PR and investor relations operations."
A law graduate, Bashir has a decade's experience in comms and has advised UK and international companies on strategy, reputation, media and investor relations, IPO and M&A transactions.
In addition to her time at Citigate Dewe Rogerson, Bashir's agency experience includes account management roles at financial PR firms Abchurch Communications and Bishopsgate Communications.
She also spent almost three years working in comms at mining firm Mano River Resources.
Commenting on her latest role, Bashir said: "I am very excited to join this diverse and dynamic team of experts and bring a holistic approach to providing market-leading strategic advice to our clients and network."
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