Xphozah 20mg Tablets
It is used to lower high phosphate levels.
Drug Class
Phosphate binder
Pharmacologic Class
Sodium-hydrogen exchanger 3 (NHE3) inhibitor
Pregnancy Category
Not available
FDA Approved
Oct 2023
DEA Schedule
Not Controlled
Overview
What is this medicine?
Xphozah is a medication used to lower high phosphorus levels in the blood for adults with kidney disease who are on dialysis. It works by blocking a protein in your gut that absorbs phosphorus from the food you eat, helping your body get rid of more phosphorus.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided to you and follow the instructions closely.
Take the first dose of the day immediately before breakfast or your first meal of the day.
Take the second dose of the day immediately before dinner, unless your doctor has given you different instructions.
Important Timing Considerations
Do not take this medication right before a dialysis session. Instead, take it right before the next meal after dialysis.
If you are unsure about when to take your medication, consult with your doctor.
If you are also taking sodium polystyrene sulfonate (SPS), take it at least 3 hours before or 3 hours after your medication.
Storing and Disposing of Your Medication
Store your tablets in their original container at room temperature, keeping the cap tightly closed.
Do not remove the antimoisture cube or packet from the container.
Keep the container in a dry place, away from the bathroom.
What to Do if You Miss a Dose
If you miss a dose, skip it and return to your normal dosing schedule.
Do not take two doses at the same time or take extra doses to make up for a missed dose.
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided to you and follow the instructions closely.
Take the first dose of the day immediately before breakfast or your first meal of the day.
Take the second dose of the day immediately before dinner, unless your doctor has given you different instructions.
Important Timing Considerations
Do not take this medication right before a dialysis session. Instead, take it right before the next meal after dialysis.
If you are unsure about when to take your medication, consult with your doctor.
If you are also taking sodium polystyrene sulfonate (SPS), take it at least 3 hours before or 3 hours after your medication.
Storing and Disposing of Your Medication
Store your tablets in their original container at room temperature, keeping the cap tightly closed.
Do not remove the antimoisture cube or packet from the container.
Keep the container in a dry place, away from the bathroom.
What to Do if You Miss a Dose
If you miss a dose, skip it and return to your normal dosing schedule.
Do not take two doses at the same time or take extra doses to make up for a missed dose.
Lifestyle & Tips
- Take Xphozah immediately before each meal or snack, as directed by your doctor.
- Continue to follow your prescribed diet for kidney disease, which often includes limiting phosphorus-rich foods.
- Report any severe or persistent diarrhea to your healthcare provider immediately.
- Do not stop taking Xphozah without consulting your doctor, even if you feel well.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
20 mg orally three times daily immediately prior to meals or snacks.
Dose Range:
20 - 20 mg
Condition-Specific Dosing:
ESRD on Dialysis:
20 mg orally three times daily immediately prior to meals or snacks.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
No dose adjustment necessary.
Moderate:
No dose adjustment necessary.
Severe:
No dose adjustment necessary.
Dialysis:
Indicated for use in adults with CKD on dialysis; no dose adjustment needed beyond standard dosing.
Hepatic Impairment:
Mild:
No dose adjustment necessary.
Moderate:
No dose adjustment necessary.
Severe:
No dose adjustment necessary.
Confidence:
Medium
Pharmacology
Mechanism of Action
Tenapanor is a locally acting inhibitor of the sodium-hydrogen exchanger 3 (NHE3), an antiporter expressed on the apical surface of enterocytes in the gastrointestinal tract. By inhibiting NHE3, tenapanor reduces the absorption of sodium from the gut, leading to increased luminal sodium and water. This also reduces paracellular phosphate absorption, thereby decreasing serum phosphorus levels in patients with chronic kidney disease (CKD) on dialysis.
Pharmacokinetics
Absorption:
Bioavailability:
Minimal systemic absorption (<1%)
Tmax:
Approximately 1.5 to 2 hours (for minimal systemic exposure)
FoodEffect:
Food increases systemic exposure slightly (AUC by 1.5-fold, Cmax by 1.3-fold), but this is not considered clinically significant due to minimal absorption.
Distribution:
Vd:
Not applicable (minimal systemic absorption)
ProteinBinding:
Not applicable (minimal systemic absorption)
CnssPenetration:
No
Elimination:
HalfLife:
Not well-defined due to minimal systemic absorption; systemic half-life is approximately 2.5 hours for the small amount absorbed.
Clearance:
Not applicable (minimal systemic absorption)
ExcretionRoute:
Primarily fecal (as unchanged drug and metabolites)
Unchanged:
Approximately 90% of the dose is recovered in feces as unchanged drug.
Pharmacodynamics
OnsetOfAction:
Within days (reduction in serum phosphorus)
PeakEffect:
Within 1-2 weeks (stable reduction in serum phosphorus)
DurationOfAction:
Maintained with continued dosing
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor for guidance:
Diarrhea (common and potentially severe): If you experience diarrhea or stomach cramps, consult your doctor for advice on managing these symptoms and preventing dehydration. Do not attempt to treat diarrhea without first consulting your doctor.
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, contact your doctor for medical advice. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor for guidance:
Diarrhea (common and potentially severe): If you experience diarrhea or stomach cramps, consult your doctor for advice on managing these symptoms and preventing dehydration. Do not attempt to treat diarrhea without first consulting your doctor.
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, contact your doctor for medical advice. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe or persistent diarrhea
- Signs of dehydration (e.g., extreme thirst, decreased urination, dizziness, dry mouth)
- Severe abdominal pain or cramping
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction and its symptoms.
If you have a bowel blockage, as this may affect the use of this medication.
If the patient is a child, as this medication is not approved for use in children under the age of 6. Do not administer this medication to a child younger than 6 years old.
Additionally, this is not an exhaustive list of all potential interactions with this medication. Therefore, it is crucial to discuss the following with your doctor and pharmacist:
All prescription and over-the-counter medications you are taking, including natural products and vitamins.
* Any existing health problems you have.
To ensure your safety, verify that it is acceptable to take this medication with all your other medications and health conditions. Never start, stop, or modify the dosage of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction and its symptoms.
If you have a bowel blockage, as this may affect the use of this medication.
If the patient is a child, as this medication is not approved for use in children under the age of 6. Do not administer this medication to a child younger than 6 years old.
Additionally, this is not an exhaustive list of all potential interactions with this medication. Therefore, it is crucial to discuss the following with your doctor and pharmacist:
All prescription and over-the-counter medications you are taking, including natural products and vitamins.
* Any existing health problems you have.
To ensure your safety, verify that it is acceptable to take this medication with all your other medications and health conditions. Never start, stop, or modify the dosage of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. If you are pregnant, planning to become pregnant, or are breast-feeding, be sure to discuss this with your doctor. This conversation will help you understand the potential benefits and risks of this medication to both you and your baby, allowing you to make an informed decision.
Overdose Information
Overdose Symptoms:
- Severe diarrhea
- Dehydration
- Electrolyte imbalances
What to Do:
There is no specific antidote for tenapanor overdose. Management should be supportive, focusing on hydration and electrolyte correction. Call 1-800-222-1222 (Poison Control) or seek immediate medical attention.
Drug Interactions
Monitoring
Baseline Monitoring
Serum Phosphorus
Rationale: To establish baseline levels and guide initial dosing.
Timing: Prior to initiation of therapy.
Serum Calcium
Rationale: To assess for potential electrolyte imbalances, though tenapanor is not expected to directly affect calcium.
Timing: Prior to initiation of therapy.
Parathyroid Hormone (PTH)
Rationale: To assess bone mineral metabolism status in CKD patients.
Timing: Prior to initiation of therapy.
Routine Monitoring
Serum Phosphorus
Frequency: Every 2-4 weeks initially, then monthly or as clinically indicated once stable.
Target: Typically 2.5-4.5 mg/dL (target for CKD-MBD varies by guideline)
Action Threshold: Adjust dose or consider alternative/adjunctive therapy if target not met or if hyperphosphatemia persists.
Serum Calcium
Frequency: Monthly or as clinically indicated.
Target: Normal range (e.g., 8.5-10.2 mg/dL)
Action Threshold: Investigate and manage any significant deviations.
Signs and Symptoms of Diarrhea
Frequency: Daily, especially during initial weeks of therapy.
Target: Not applicable
Action Threshold: If severe diarrhea occurs, consider dose reduction or temporary discontinuation. Advise patient to contact healthcare provider.
Symptom Monitoring
- Diarrhea (frequency, severity, abdominal discomfort)
- Nausea
- Abdominal pain
- Flatulence
Special Patient Groups
Pregnancy
Limited human data on tenapanor use in pregnant women are insufficient to inform a drug-associated risk for major birth defects or miscarriage. Animal studies have shown adverse developmental outcomes at exposures higher than clinical exposure. Use only if the potential benefit justifies the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
Limited data; potential for risk based on animal studies at high exposures.
Second Trimester:
Limited data; potential for risk based on animal studies at high exposures.
Third Trimester:
Limited data; potential for risk based on animal studies at high exposures.
Lactation
It is not known whether tenapanor is excreted in human milk. Due to the potential for serious adverse reactions in the breastfed infant, including dehydration, advise women not to breastfeed during treatment with Xphozah.
Infant Risk:
Potential for serious adverse reactions, including dehydration, due to the mechanism of action (NHE3 inhibition).
Pediatric Use
Safety and effectiveness in pediatric patients have not been established. Xphozah is not recommended for use in pediatric patients. (Note: Tenapanor for IBS-C is contraindicated in patients younger than 6 years of age due to risk of serious dehydration).
Geriatric Use
No overall differences in safety or effectiveness were observed between elderly patients (65 years and older) and younger patients. No dose adjustment is necessary based on age.
Clinical Information
Clinical Pearls
- Xphozah is a novel, non-calcium, non-metal based phosphate binder, offering an alternative for patients who may not tolerate or respond to traditional binders.
- Its mechanism of action (NHE3 inhibition) is unique among phosphate-lowering agents, reducing phosphate absorption via a paracellular pathway.
- The primary side effect is diarrhea, which can be managed by dose reduction or temporary discontinuation. Patients should be counseled on this potential side effect.
- Minimal systemic absorption means a low risk of systemic drug-drug interactions, making it a potentially safer option for polypharmacy patients.
- It must be taken immediately before meals or snacks for optimal efficacy.
Alternative Therapies
- Calcium acetate (PhosLo, Calphron)
- Sevelamer carbonate (Renvela)
- Sevelamer hydrochloride (Renagel)
- Lanthanum carbonate (Fosrenol)
- Sucroferric oxyhydroxide (Velphoro)
- Ferric citrate (Auryxia)
Cost & Coverage
Average Cost:
Highly variable, typically >$1000 per 30 tablets
Insurance Coverage:
Specialty Tier / Tier 4-5 (requires prior authorization)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it occurred.