system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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is distributed; The investigation will be conducted in accordance with good clinical practices, including review and approval of the study by an independent ethics panel and informed consent of the study subjects; The drug, Interferon Alfa-n3, does not present an imminent hazard to public health, either in the United States, if the drug were to be reimported, or in the countries in which it is distributed; The drug, Interferon Alfa-n3, is labelled in accordance with the laws of the countries in which it is distributed. I have reviewed the attached labels and the current Certificate of Analysis against the specifications and agree with the above statements that these meet the laws of the countries in which the product will be distributed. Signature: __________________________________ Date: ______________________ Printed Name: Saleh Al- Rashid Title: Chairman and CEO Company: Scientific Products Pharmaceutical Co. LTD {***} Confidential portions of this exhibit have been redacted and filed separately with the Commission pursuant to a confidential treatment request in accordance with Rule 24b-2 of the Securities Exchange Act of 1934, as amended. Page 12 of 28 Certificate of Analysis {***} {***} Confidential portions of this exhibit have been redacted and filed separately with the Commission pursuant to a confidential treatment request in accordance with Rule 24b-2 of the Securities Exchange Act of 1934, as amended. Page 13 of 28 Label information enlarged for ease of read. {***} Enlarged Label: {***} Caution: Limited by Federal (US) Law to Investigational Use. Manufactured For: Hemispherx Biopharma, Inc. Philadelphia, PA 19103 (U.S.A.) Actual Label: {***} {***} Confidential portions of this exhibit have been redacted and filed separately with the Commission pursuant to a confidential treatment request in accordance with Rule 24b-2 of the Securities Exchange Act of 1934, as amended. Page 14 of 28 Exhibit 2 Study Protocol Synopsis A Compassionate Use Protocol Using Natural Leukocyte Interferon (Alfa-n3) for Individual Treatment of Symptomatic Patients with Middle East Respiratory Syndrome (MERS) {***} {***} Confidential portions of this exhibit have been redacted and filed separately with the Commission pursuant to a confidential treatment request in accordance with Rule 24b-2 of the Securities Exchange Act of 1934, as amended. Page 15 of 28 Exhibit 3 Business Plan {***} Confidential portions of this exhibit have been redacted and filed separately with the Commission pursuant to a confidential treatment request in accordance with Rule 24b-2 of the Securities Exchange Act of 1934, as amended. Page 16 of 28 Exhibit 4 TECHNICAL / QUALITY AGREEMENT 1. Parties This Quality Agreement is entered by and between Scientific Products Pharmaceutical Co. LTD., a pharmaceutical company with its primary offices located at Tahlia Street, P.O Box 10485, Riyadh 11433 Saudi Arabia ("SCIEN") and Hemispherx Biopharma, Inc. 783 Jersey Avenue, New Brunswick, New Jersey 08901(HEMISPHERX). 2. Purpose The purpose of this Quality Agreement is to clearly define the quality operating procedures, duties and responsibilities to be employed by SCIEN and HEMISPHERX in the conduct of activities by SCIEN for Hemispherx Biopharma, Inc. The objective of these procedures and this Quality Agreement is assurance that services are conducted in a timely, consistent and uniform manner and in accordance with current laws, directives, regulations and guidelines, as may be applicable to the specific project(s). These requirements may include those defined by the U.S. FDA's regulations At 21CFR314.80 (Post-marketing reporting of adverse drug experiences for drugs), 21CFR312.32 (IND safety reporting) 21CFR600.80 (Post marketing reporting of adverse experiences for biologics) 21CFR Parts 210 and 211 ("current Good Manufacturing Practices" or "cGMPs") with particular interest in 21CFR211.1.42 (Warehousing), 21CFR211.150 (Distribution), 21CFR211.204 (Returned drug) and 21CFR211.208 (Drug product salvaging), ICH Guidance for Industry: E6 Good Clinical Practice Consolidated Guidance and/or others that may be appropriate for the particular project. 3. Scope This Quality Agreement is to be applied to the activities performed by SCIEN, for HEMISPHERX as specifically defined by the Sales, Marketing, Distribution, and Supply Agreement January ___, 2016 ("Agreement") to which this Quality Agreement is an integral Exhibit. In the event of a conflict between the terms of the Agreement and this Quality Agreement, the terms of the Agreement shall control. Unless otherwise stated in these documents, SCIEN shall follow its Standard Operating Procedures ("SOPs") with respect to the activities it shall carry out in accordance with the Agreement. Copies of all relevant SOPs shall be provided to HEMISPHERX for review during audits. 4. Confidentiality The information and procedures contained in this Quality Agreement are confidential and subject to the terms and conditions of the confidentiality provisions as set forth in the Confidential Disclosure Agreement
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Extract the exact clause related to "Covenant Not To Sue" from the excerpt above.