Senior Administrative Assistant, (US)

CellCentric Limited; Burlington (MA); On-site; USD 55,000 - 85,000; Full time

Job summary

CellCentric is seeking a Senior Administrative Assistant to provide high-quality administrative and operational support to the organization, with primary responsibility for the Burlington, MA office. The role requires excellent judgment, organization, and adaptability in a fast-paced biotech environment.

You will support senior leaders, manage complex calendars, coordinate travel, and handle confidential information with discretion.

Qualifications

• 5+ years of administrative, executive support, office management, or related experience; experience supporting senior leaders strongly preferred.
• Proven ability to manage multiple priorities, calendars, deadlines, and stakeholders in a fast-moving environment.
• Strong proficiency with Microsoft Outlook, Word, PowerPoint, Excel, Teams, and other standard business applications.
• Excellent written and verbal communication skills and the ability to interact professionally with employees, executives, Board members, visitors, vendors, and external partners.
• Strong attention to detail, follow-through, and organizational skills.
• Sound judgment and discretion with confidential information.
• Proactive, resourceful, independent, and able to solve problems without direction.
• Flexible and able to shift priorities as the organization grows.
• Experience in biotechnology, pharmaceutical, life sciences, or fast-paced professional environments is preferred.
• Ability to work both independently and collaboratively within a team.

Responsibilities

• Provide proactive administrative support to senior leaders, including calendar management, coordinating meetings, travel, and expense reporting.
• Own day-to-day administration and office operations for the Burlington office, ensuring resources and support for U.S. employees.
• Coordinate internal and external meetings, rooms, AV, catering, materials, and logistics.
• Support company and leadership meetings, events, and other U.S.-based activities, including venues and travel.
• Serve as a key administrative resource for U.S. employees, directing questions to appropriate resources.
• Partner with HR on onboarding/offboarding and first-day logistics for U.S. employees.
• Coordinate visitors, deliveries, building access, and reception needs at the Burlington office.
• Liaise with facilities, IT, vendors to maintain office and equipment.
• Manage office supplies and inventory; identify cost-saving opportunities.
• Create/edit/proofread/format presentations, documents, reports, and communications.
• Handle confidential information with discretion and professionalism.
• Anticipate needs, identify issues, and take initiative with minimal direction.
• Provide additional administrative and project support across the U.S. organization as needed.

Job description

The Senior Administrative Assistant provides high-quality administrative and operational support to CellCentric’s organization, including a variety of senior leaders, while taking primary responsibility for the day-to-day administration of our Burlington, Massachusetts office. This highly visible role requires excellent judgment, organization, flexibility, and the ability to anticipate needs in a fast-paced, growing biotechnology company. This individual will contribute to the success of the team and organization while upholding our core working behaviors of Trust and Respect, Communication and Feedback, Accountability and Reliability, Objectivity, and Team Balance and Enablement.

Key Responsibilities

• Provide proactive administrative support to a variety of senior leaders, including complex calendar management, meeting coordination, travel arrangements, expense reporting, and other administrative needs.
• Own the day-to-day administration and smooth operation of the Burlington office, ensuring U.S. employees have the resources, supplies, equipment, and workplace support they need.
• Coordinate internal and external meetings, including scheduling, meeting rooms, technology and AV requirements, catering, materials, and logistics.
• Support company meetings, leadership meetings, employee events, and other U.S.-based activities, including venue, hotel, restaurant, and travel coordination as needed.
• Serve as a key administrative resource for U.S. employees, helping address day-to-day office and operational needs and directing questions to the appropriate internal resources.
• Partner with HR to support onboarding and offboarding of U.S. employees, including workplace preparation, first-day logistics, and related coordination.
• Coordinate visitors, deliveries, building access, reception needs, and other Burlington office logistics.
• Liaise with building management, facilities providers, IT support, and other vendors to ensure the office and equipment are well maintained.
• Manage office supplies and inventory, coordinate with vendors, and identify opportunities to improve efficiency and manage costs.
• Create, edit, proofread, and format presentations, documents, reports, correspondence, and other business materials.
• Handle confidential and sensitive information with appropriate discretion and professionalism.
• Anticipate administrative and operational needs, identify issues, and take initiative to resolve them with minimal direction.
• Provide additional administrative and project support across the U.S. organization as business needs evolve.

Skills and Qualifications

• 5+ years of administrative, executive support, office management, or related experience; experience supporting senior leaders strongly preferred.
• Demonstrated ability to manage multiple priorities, calendars, deadlines, and stakeholders in a fast-moving environment.
• Strong proficiency with Microsoft Outlook, Word, PowerPoint, Excel, Teams, and other standard business applications.
• Excellent written and verbal communication skills and the ability to interact professionally with employees, executives, Board members, visitors, vendors, and external partners.
• Strong attention to detail, follow-through, and organizational skills.
• Sound judgment and demonstrated ability to handle confidential or sensitive information.
• Proactive, resourceful, and comfortable working independently and solving problems without waiting for direction.
• Flexible and willing to shift priorities as the needs of a growing organization change.
• Experience in biotechnology, pharmaceutical, life sciences, or another fast-paced professional environment is preferred.
• Ability to work both independently and collaboratively within a team.

Working Behaviors (Core Expectations)

• Trust and Respect: Act with integrity, honesty, and openness to build strong, credible relationships.
• Communication and Feedback: Share information clearly, listen actively, and engage in a culture of constructive feedback.
• Accountability and Reliability: Take ownership for performance, be dependable, and support others to achieve collective goals.
• Objectivity: Align on common objectives and use facts and data to reach fair, effective decisions.
• Team Balance and Enablement: Contribute to balanced roles within the team, support delegation, and help colleagues reach their full potential.

Why Join Us?

At CellCentric, we believe success is built on great teams. By embodying these working behaviors, every member contributes to a high-performing, supportive, and inclusive culture where individuals and the business thrive together.