Please select the eligibility criteria that correspond to the clinical trial below.
Title: Phase II Study of the Effect of Oral Cromolyn Sodium on Uremic Pruritus and Serum Tryptase Levels of Hemodialysed Patients
Brief Summary: Pruritus is a major disorder among the skin derangements in advanced renal failure. Recent information suggests that interactions between dermal mast cells and distal ends of nonmyelinated C fibers may be important in the precipitation and regulation of the sensory stimuli.Patients having uremic pruritus have been noted to have increased levels of plasma histamine and tryptase as well as increased numbers of dermal mast cells.Cromolyn sodium is a mast cell stabilizing agent that inhibits degranulation of mast cells and the release of histamine, tryptase, and leukotrienes. It is hypothesized that oral cromolyn sodium may attenuate uremic pruritus by decreasing serum tryptase level.


Options:
A: Key Inclusion Criteria:

To be eligible for inclusion into the Double-blind Phase of the study, a patient must meet the following criteria:

* Has end-stage renal disease (ESRD) and has been on hemodialysis 3 times per week for at least 3 months prior to the start of screening;
* Has at least 2 single-pool Kt/V measurements ≥1.2, or at least 2 urea reduction ratio measurements ≥65%, or 1 single pool Kt/V measurement ≥1.2 and 1 urea reduction ratio measurement ≥65% on different dialysis days during the 3 months period prior to screening;
* Prior to randomization:

  * Has completed Worst Itching Intensity NRS worksheets up to 8 days prior to 1st dose;
  * Has a mean baseline Worst Itching Intensity NRS indicative of moderate to severe uremic pruritus.
* To be eligible for inclusion into the Open-label Extension Phase of the study, each patient will have to fulfill the additional key following criteria at the time of entry into the Open-label Extension Phase:

  * Has received at least 30 doses of the planned 36 doses of study drug during the Double-blind Phase of this study;
  * Continues to meet inclusion criteria.

Key Exclusion Criteria:

A patient will be excluded from the Double-blind Phase of the study if any of the following criteria are met:

* Known noncompliance with dialysis treatment that in the opinion of the investigator would impede completion or validity of the study;
* Scheduled to receive a kidney transplant during the study;
* New or change of treatment received for itch including antihistamines and corticosteroids (oral, IV, or topical) within 14 days prior to screening;
* Received another investigational drug within 30 days prior to the start of screening or is planning to participate in another clinical study while enrolled in this study;
* Has pruritus only during the dialysis session (by patient report);
* Is receiving ongoing ultraviolet B and anticipates receiving such treatment during the study;
* Participated in a previous clinical study with CR845.
* A patient will be excluded from the Open-label Extension Phase of the study if any of the additional key following criteria are met at the time of entry into the Open-label Extension Phase:

  * Completed the Double-blind Phase of this study but exhibited adverse events during the course of the Treatment Period that may preclude continued exposure to the study drug;
  * Was noncompliant with protocol procedures during the Double-blind Phase of this study which is indicative of an inability to follow protocol procedures.
B: Inclusion Criteria:

* Willingness to sign an informed consent
* Stable haemodialysis treatment for more than 3 months, undergoing 2 to 3 times haemodialysis a week for 4 to 5 hours per session
* middle or large molecules retention defined as immunoreactive parathyroid hormone (iPTH) \> 400 pg/mL, β2MG\>5000 pg/ml、CRP\>10mg/l.
* Refractory pruritus, carpal tunnel syndrome, restless leg syndrome, hyperparathyroidism or other refratory complications.

Exclusion Criteria:

* Incapable or reluctant to sign the informed consent or comply the schedule.
* platelet (PLT) count\<60×109/L or disturbance in coagulation, tendency of severe bleeding or acute bleeding.
* Severe hypotension and heart or lung insufficiency
* Known hypersensitive or contradiction or intolerance to dialyzer or adsorbents
* Attend to other clinic trial now or in recent 30 days
C: Inclusion Criteria:

* Patients who have end-stage renal disease (ESRD) on maintenance hemodialysis more than twice weekly for at least three months and suffered from uremic pruritus.
* 20 Years and older
* Definition of uremic pruritus:

Patients were considered to have pruritus if they had either of the following conditions:

* at least 3 episodes of itch during a period of 2 weeks or less, with the symptom appearing a few times a day, lasting at least a few minutes, and troubling the patient
* he appearance of an itch in a regular pattern during a period of 6 months, but less frequently than listed above.

To be defined as "uremic," the pruritus had to appear shortly before the onset of dialysis, or at any time after that, without evidence of any other active disease that could explain the pruritus.

-Patients who suffer from severe pruritus unresponsive to topical emollient and corticosteroids, and were diagnosed as having uremic pruritus by dermatologists

Exclusion Criteria:

1. All patients with pruritus attributable to any other causes, such as scabies or other evident skin diseases (atopic dermatitis, psoriasis, generalized dermatitis, pediculosis, urticaria ...etc), and any medication with potential pruritic properties.
2. Patients whose pruritus occurred only during dialysis
3. Patients received oral drugs with presumed antipruritic effect, including benzodiazepines, muscle relaxants, opioid analgesics, tricyclic antidepressants and antiepileptic drugs, or ultraviolet B phototherapy in the past one week prior to participate in this trial or during the trial.
4. Concomitant elevation of liver enzymes (GOT: male \>37 U/L, female:\>31 U/L, GPT: male \>41 U/L, female:\>31U/L), alkaline phosphatase (ALP\>104U/L), bilirubin (T-bil\>1.2 mg/dL), serum phosphorus (\>7 mg/dl), serum parathyroid hormone (\>300 pg/ml).
5. Patients who have the history of allergy to pregabalin, any acute illness, liver cirrhosis, hepatic failure, decompensated heart failure, inability to give informed consent, or poor compliance.
6. Patients with uncontrolled psychiatric disease, active malignancy, and untreated hypothyroidism.
7. Female patients who are pregnant, are nursing, or want to become pregnant.
D: Inclusion Criteria:

* Hemodialysis patients \> 18 yo suffering from pruritus for at least 6 weeks, and who have not responded to other drugs
* Willing and able to give informed concent

Exclusion Criteria:

* Known dermatologic, liver, metabolic disease, or any other disease or condition other than ESRD that causes pruritus
* Lactase deficiency

Answer: D