Patient case (clinical description): A 23-year-old female has prolonged oral bleeding immediately after a tooth extraction.  Despite several interventions, the bleeding persists for hours and stops only after desmopressin (DDAVP) administration.  The patient has heavy menstrual cycles each month.  She has no other medical problems and takes no medications.  Her mother and grandmother have also had excessive bleeding during menstrual period.  Review of systems is positive for mild bruising on his legs. Laboratory findings reveal a normal platelet count and an abnormal ristocetin cofactor assay, as well as CB <= 0.30 IU/mL and FVIII:C <= 0.40 IU/mL.

Patient's own account: I'm a 23 woman and I went to the ER because of non-stop bleeding after my tooth extraction. I tried to make the bleeding stop but it just kept going for hours and it finally stopped when I took some medication called DDAVP. I usually have heavy periods, just like my mom and grandma had. I don't have any other medical condition and I don't take any other medication. The doctor noticed the bruises on my legs. I had to do some lab tests. I had a normal platelet count but an abnormal ristocetin cofactor assay. I had low CB and FVIII:C levels.

Clinical trial: Phase I Study of Direct Coagulation Factor Xa Inhibitor SYHA136 Tablets in Chinese Healthy Volunteers

Eligibility criteria:
Inclusion Criteria:

          1. When subject signs the informed contest, 18≤ age ≤ 40, Male or female;

          2. Body weight: male ≥50 kg, female ≥45 kg. Body mass index (BMI) of 19.0 to 26.0 kg/m²,
             inclusive;

          3. Subject's with normal or or abnormity without clinical significance judged by the
             investigator by physical examination, vital signs, electrocardiogram, blood routine,
             blood biochemistry, coagulation tests, fecal occult blood, urine routine, serological
             tests and other important indicators;

          4. All subjects who adopt effective non-hormonal contraceptive measures (such as condoms,
             intrauterine devices without drugs, etc.) from the signing of informed consent to
             three months after the end of the study;

          5. Subjects who voluntarily signed the informed consent and are able to cooperate to
             complete the test according to the protocal.

        Exclusion Criteria:

          1. Allergic history to more than one drug or other serious allergic rhistory;

          2. Serious diseases of the central nervous system, cardiovascular system, digestive
             system, respiratory system, urinary system, blood system, metabolic disorders or other
             diseases (such as history of psychosis, malignant tumors, etc.)In the past or now,
             which were not suitable for clinical trials.

          3. History of abnormal bleeding or coagulation disorders (e.g. prone to bruising, gum
             bleeding, prolonged bleeding after tooth extraction, joint hemorrhage, menorrhagia,
             postpartum hemorrhage, vitamin K deficiency, haemorrhagic diseases caused by acquired
             coagulation factor antibodies, trauma, wound or post-operative bleeding, etc.);

          4. History of severe head trauma in 2 years;

          5. Severe gastrointestinal diseases occurred within three months before signing informed
             consent, which affected drug absorption;

          6. Have a disease which Haemorrhage could cause serious consequences, such as peptic
             ulcer;

          7. Had undergone surgery within six months before signing the informed consent; planned
             to undergo surgery (including cosmetic surgery, dental surgery and oral surgery)
             within two weeks after the end of the trial; or planned to take part in vigorous
             exercise (including physical contact exercise or collision exercise) during the trial;

          8. Bleed or donated more than 400 mL within three months before signing informed consent,
             or planned to donate blood during the study or within one month after the end of the
             trial;

          9. Have taken any prescription drugs, nonpreserip drugs, biological products, traditional
             Chinese medicines, herbal medicines, vitamin dietary supplements and health products
             within four weeks before signing the informed consent or use oral long-acting
             contraceptives or implanted long-acting contraceptives;

         10. Subjects participating in other clinical trials and taking trial products, or
             participated in any other clinical trials of drugs within three months before signing
             the informed consent;

         11. History of drugs or drug abuse or alcoholics or drug abuse screening shows positive
             response;

         12. current or past alcoholics (drinking more than 14 standard units per week, 1 Standard
             unit containing 14g alcohol, such as 360 mL beer or 40% spirits or 150 mL wines with
             45 mL alcohol), or alcohol breath test positive;

         13. Smokers: The average daily smoking volume was more than 5 cigarettes within six months
             before signing the informed consent;

         14. Habitually consume excessive caffeine-containing beverages or foods, or foods that may
             affect drug metabolism within four weeks before signing informed consent. Such as:
             coffee (no more than 1100 mL per day), tea (no more than 2200 mL per day), cola (no
             more than 2200 mL per day), functional drinks (no more than 1100 mL per day),
             chocolate (no more than 510 g per day);

         15. Positive with serum immunological test for HBsAg, Anti-HCV, Anti-HIV or Anti-TP;

         16. QTc interval≥450 ms, electrocardiogram abnormality with clinical significance, or
             prolonged history of QTc interval;

         17. Abnormal results of chest X-ray (posterior and anterior) with clinical significance;

         18. Female subjects: positive pregnancy tests or pregnant or breast-feeding or planning to
             conceive, who plan to conceive within three months from the signing of informed
             consent to the end of the study; male subjects: whose partners plan to conceive or
             plan to donate sperm within three months from the signing of informed consent to the
             end of the study;

         19. Not suitable for this trial according to the investigator.
No condition on gender to be admitted to the trial.
Accepts Healthy Volunteers
Subject must be at least 18 Years old.
Subject must be at most 40 Years

Eligibility (NLI label): Contradiction