AbbVie continuously evaluates its operations to identify opportunities to optimize its manufacturing and R&D operations, commercial infrastructure and administrative costs and to respond to changes in its business environment. As a result, AbbVie management periodically approves individual restructuring plans to achieve these objectives. As of March 31, 2024 and 2023, no such plans were individually significant. Restructuring charges were $15 million for the three months ended March 31, 2024 and $27 million for the three months ended March 31, 2023. These charges are recorded in cost of products sold, R&D expense and SG&A expense in the condensed consolidated statements of earnings based on the classification of the affected employees or the related operations.

The following table summarizes the cash activity in the restructuring reserve for the three months ended March 31, 2024:


(in millions)
Accrued balance as of December 31, 2023	$	196
Restructuring charges	14
Payments and other adjustments	(32)
Accrued balance as of March 31, 2024	$	178

Following the closing of the Allergan acquisition, AbbVie implemented an integration plan designed to reduce costs, integrate and optimize the combined organization and incurred total cumulative charges of $2.5 billion through December 31, 2023. These costs consisted of severance and employee benefit costs (cash severance, non-cash severance including accelerated equity award compensation expense, retention and other termination benefits) and other integration expenses. The Allergan integration plan was substantially complete as of December 31, 2023 and the remaining accrual as of March 31, 2024 is not significant.

The following table summarizes the prior year charges associated with the Allergan acquisition integration plan:


	Three months ended March 31,
(in millions)		2023
Cost of products sold		$	14
Research and development		—
Selling, general and administrative		44
Total charges		$	58