It's possible to edit:
the name of the campaign
the address that replies should be forwarded to
the links in the campaign
These can all be edited in the campaign's Summary page (accessed through Campaigns > Email > Sent and then selecting a campaign's Summary icon).
Campaign summary page
The campaign summary page lists the details of the campaign.
Edit the campaign name
In the upper left corner, the campaign name is shown. Select the name to edit it. Once you've entered the new name, select the green tick.
Edit the forwarding address
To edit the address that replies are forwarded to, select the (Edit) link at the end of the Forward replies to: line.
Replies may be forwarded to one address at a time only.
If the field is blank, replies won't be forwarded.
You can edit links after a campaign has been sent. To do this, select the (View / edit) link at the end of the Hyperlinks: line.
You'll be shown a table of links which can be edited. Don't forget to save your changes after editing.
You won't be able to change links that have been set to 'Do not track'.