English to Czech Medical Medical: Pharmaceuticals clinical trial agreement

In this context: "This Agreement is entered into between the parties hereto on principal to principal basis."
Further down: "Nothing contained in this Agreement shall be construed to imply a joint venture, employment, partnership, or principal-agent relationship between the Institution/Investigator and the Sponsor"

Principal - agent could be zmocnitel - zmocněnec, but could "zmocnitel" be used in the first sentence above? Please provide complete wording of translation of the first sentence ".... on principal to principal basis." Many thanks.

Please bear in mind that aside of "agent", I also need to translate "representative" and "designee" by corresponding different terms for the same agreement. This will be subject of following requests.