Phase III, Prospective, Multinational, Multicenter, Randomized, Controlled, Two-arm, Double Blind Study to Assess Efficacy and Safety of D-PLEX Administered Concomitantly with the Standard of Care (SoC), Compared to a SoC Treated Control Arm, in Prevention of Post Abdominal Surgery Incisional Infection.

D-PLEX is a new formulation of extended controlled release of Doxycycline in the applied area for about 30 days. This study is aimed to assess the safety and efficacy of D-PLEX in prevention of post abdominal surgery incisional infection.

The study population includes male and female, 18 years old and above at screening, undergoing an elective colorectal surgery involving colon or rectal resection, with or without a stoma formation, that includes at least 1 incision that is > 20cm (target incision).

Eligible and willing subjects will be randomly allocated into 2 blinded study arms, either to the investigational arm (D-PLEX + SoC) or to the control arm (SoC only) in a 1:1 ratio. Subjects will be stratified by type of prophylactic SoC (IV antibiotic only, IV antibiotic with mechanical bowel preparation or IV antibiotic with oral antibiotics combined with mechanical bowel preparation) and by region (US versus Europe + Israel).

D-PLEX will be applied during the surgery at the final stage of incision closure. All patients will be followed up for additional 5 visits over 2 months, for safety and incisional wound assessment. This will include blood tests for hematology and chemistry as well as physician's assessment of the incisional wound.

Inclusion Criteria:

1. Subjects undergoing an elective colorectal surgery involving resection, with or without a stoma formation, that includes at least 1 abdominal incision that is >20cm (target incision).
2. Subjects are preoperative hemodynamically stable. (BP≤180/110 and >90/60 mmHg, and HR≤120 and >60 bpm, and temperature ≤37.50C and >35.50C).
3. Male or non-pregnant female.
4. Female of child-bearing potential should have a negative pregnancy test (serum or urine dipstick) prior to index procedure.
5. Subjects' age 18 years old and above at screening.
6. Subjects who sign the written Informed Consent Form.
7. Subjects who are willing and able to participate and meet all study requirements.
8. Survival expectancy of at least 60 days post randomization.

Exclusion criteria:

1. Subjects with suspected/diagnosed intestinal perforation, intra-abdominal abscess, or any emergency/urgent colorectal surgery with acute intestinal obstruction (ex. toxic colitis, ileus/sub-ileus, megacolon, diverticulitis, volvulus, etc.)

2. Subjects who underwent an intra-abdominal surgery within the last 6 months prior to randomization.

3. Subjects with any preoperative active infection or who are receiving any antibiotic therapy in the past 1 week prior to randomization, excluding pre-operative prophylaxis.

4. Subjects undergoing concomitant major procedures in addition to the colorectal resection.

   Female sterilization surgeries (i.e. salpingo-oophorectomy etc.), involvement of a small bowel procedure or cholecystectomy may be allowed, pending an advanced consultation and approval from the Sponsor .

5. Subjects who received any anti-cancer treatment within the last 4 weeks of surgery.

6. Subjects who received radiation for colorectal cancer to the abdomen and/or pelvis area, within the last 4 weeks of the planned abdominal surgery.

7. Subjects who received oral or IV Doxycycline or Tetracycline family antibiotics during the past 4 weeks prior to randomization.

8. Subjects with known allergy to Doxycycline and/or to the tetracycline family of drugs or to the D-PLEX's excipients.

9. Subjects with known allergies to more than 3 substances (an allergy questionnaire will be completed during the screening process).

10. Subjects with history of severe allergic reaction to any substance, having required treatment with intravenous steroids/intramuscular epinephrine, or who in the opinion of the PI is at high risk of developing severe allergic reactions.

11. Subjects with End Stage Renal Disease (ESRD/ CKD stage 5).

12. Subjects with severe hepatic impairment.

13. Subjects with chronic urticaria.

14. Subjects diagnosed with CVA within the past 6 months prior to randomization.

15. Subjects who underwent any abdominal surgery and current planned index surgery involves re-opening the scar of a prior abdominal surgery performed within the last 3 years.

16. Any subject with an active malignancy or with malignancy that has not been in complete clinical remission and without maintenance chemo or immunotherapy for at least 3 years.

    Excluding: Subjects with potentially resectable non-metastatic colorectal cancer, that is the reason for the index surgery.

    Subjects who have had carcinoma in situ (or other cancer "in situ = Stage 0"), or squamous cell carcinoma of the skin, or basal cell carcinoma of the skin.

    Subjects with any additional non-violent cancer that does not require treatment 4 weeks prior to the surgery, and throughout the entire study duration.

17. Subjects with other concurrent severe and/or uncontrolled medical condition.

18. Psychiatric or any other disorder that compromises ability to provide informed consent for participation in this study.

19. Chronic alcoholic or drug abuse subjects.

20. Pregnant or breast-feeding women or women of child-bearing age who refuse or are prohibited of using an effective contraceptive method of birth control throughout study participation, including the safety follow-up period.

21. Subjects who received any investigational drug within 30 days or 5 half-lives prior to randomization to the study (whichever is longer) and through the study.

22. Subjects participating in any other interventional study.

23. Subjects who in the opinion of Investigator, are not eligible to participate in the study and/or to comply with the protocol requirements (e.g. due to a cognitive or medical condition).

This is a double-blind clinical trial. The sponsor, the subjects, outcomes assessor and all staff involved in the collection and recording of the clinical and laboratory data, based on which the independent adjudication committee will perform their assessment, will be blind to treatment assignment. In addition, all aspects of data management and clean-up will be done in blinded datasets.

The study site personnel, who perform the index surgery (Operation room staff), will be trained not to disclose the treatment arm to the blinded Investigator, to the subject, his/her family, to other health care providers not present during the surgery or to the study Sponsor representatives. Wound assessment throughout the study follow-up visits will be done by a blinded Investigator, that will not be involved in the surgery. An emergency card containing the Study Name, NIH number, Center Name/number, PI's name and contact details will be provided to the subjects.