Severance and Retention Costs (Tables)

9 Months Ended

Sep. 30, 2021

Akcea Merger [Member]

Severance and Retention Costs [Abstract]

Severance and Retention Costs

As a result of the Akcea Merger in October 2020, we began recognizing severance and retention expenses in the fourth quarter of 2020. The following table summarizes our total estimated severance and retention expenses related to the Akcea Merger (in millions):

	Severance and Retention Expenses
Total estimated expenses	$	27.2
Expenses incurred from inception to September 30, 2021		27.0
Remaining estimated expenses to be recognized through October 2021	$	0.2

The following table summarizes our severance and retention expenses related to the Akcea Merger that we recognized during the three and nine months ended September 30, 2021 (in millions):

	Three Months Ended September 30, 2021		Nine Months Ended September 30, 2021
Research, development and patent expenses	$	1.3	$	5.1
Selling, general and administrative expenses		0.6		6.6
Total	$	1.9	$	11.7

The following table summarizes the severance and retention reserve amounts related to the Akcea Merger that we included in accrued compensation for the period indicated (in millions):

	Nine Months Ended September 30, 2021
Beginning balance as of January 1, 2021	$	14.7
Amounts expensed during the period		13.5
Reserve adjustments during the period		(1.8	)
Net amount expensed during the period		11.7
Amounts paid during the period		(20.6	)
Ending balance as of September 30, 2021	$	5.8

Restructured European Operations [Member]

Severance and Retention Costs [Abstract]

Severance and Retention Costs

In December 2020, we entered into a distribution agreement with Sobi for TEGSEDI and WAYLIVRA in Europe. As a result, we restructured our European Operations, or Restructured European Operations. In the fourth quarter of 2020, we began recognizing severance and retention expenses related to our Restructured European Operations. The following table summarizes our total severance and retention expenses related to our Restructured European Operations (in millions):

	Severance and Retention Expenses
Total estimated expenses	$	14.2
Expenses incurred from inception to September 30, 2021		14.0
Remaining estimated expenses to be recognized through October 2021	$	0.2

The following table summarizes the severance and retention expenses related to our Restructured European Operations that we recognized during the three and nine months ended September 30, 2021 (in millions):

	Three Months Ended September 30, 2021		Nine Months Ended September 30, 2021
Research, development and patent expenses	$	0.5	$	0.6
Selling, general and administrative expenses		0.1		1.1
Total	$	0.6	$	1.7

The following table summarizes the severance and retention reserve amounts related to our Restructured European Operations that we included in accrued compensation for the period indicated (in millions):

	Nine Months Ended September 30, 2021
Beginning balance as of January 1, 2021	$	12.4
Amounts expensed during the period		2.5
Reserve adjustments during the period		(0.8	)
Net amount expensed during the period		1.7
Amounts paid during the period		(13.4	)
Ending balance as of September 30, 2021	$	0.7

Restructured North American TEGSEDI Operations [Member]

Severance and Retention Costs [Abstract]

Severance and Retention Costs

The following table summarizes the severance expenses related to our Restructured North American TEGSEDI Operations that we recognized during the second quarter of 2021 (in millions):

	Three Months Ended June 30, 2021
Research, development and patent expenses	$	2.3
Selling, general and administrative expenses		7.1
Total	$	9.4

The following table summarizes the severance reserve amounts related to our Restructured North American TEGSEDI Operations that we included in accrued compensation for the period indicated (in millions):

	Nine Months Ended September 30, 2021
Beginning balance as of January 1, 2021	$	—
Amounts expensed during the period		9.4
Amounts paid during the period		(9.2	)
Ending balance as of September 30, 2021	$	0.2