Patiromer Explained

Tradename:Veltassa
Dailymedid:Patiromer
Pregnancy Au:B1
Routes Of Administration:By mouth
Atc Prefix:V03
Atc Suffix:AE09
Legal Au:S4
Legal Au Comment:[1] [2]
Legal Ca:Rx-only
Legal Ca Comment:[3]
Legal Us:Rx-only
Legal Eu:Rx-only
Bioavailability:Not absorbed
Metabolism:None
Onset:7 hrs
Duration Of Action:24 hrs
Excretion:Feces
Index2 Label:Calcium salt
Cas Number:1260643-52-4
Cas Number2:1208912-84-8
Unii:1FQ2RY5YHH
Pubchemsubstance:135626866
Drugbank:DB09263
Chemspiderid:None
Kegg:D10148
Kegg2:D11037
Chembl:2107875
Synonyms:RLY5016
Chemical Formula:[(C<sub>3</sub>H<sub>3</sub>FO<sub>2</sub>)<sub>182</sub>·(C<sub>10</sub>H<sub>10</sub>)<sub>8</sub>·(C<sub>8</sub>H<sub>14</sub>)<sub>10</sub>]n
[Ca<sub>91</sub>(C<sub>3</sub>H<sub>2</sub>FO<sub>2</sub>)<sub>182</sub>·(C<sub>10</sub>H<sub>10</sub>)<sub>8</sub>·(C<sub>8</sub>H<sub>14</sub>)<sub>10</sub>]n (calcium salt)

Patiromer, sold under the brand name Veltassa, is a medication used to treat high blood potassium.[4] It is taken by mouth.[4] It works by binding potassium in the gut.

Common side effects include constipation, low blood magnesium, and abdominal pain.[4]

It was approved for medical use in the United States in October 2015,[5] [4] and in the European Union in July 2017.

Medical uses

Patiromer is used for the treatment of hyperkalemia, but not as an emergency treatment for life-threatening hyperkalemia, as it acts relatively slowly. Such a condition needs other kinds of treatment, for example calcium infusions, insulin plus glucose infusions, salbutamol inhalation, and hemodialysis.

Typical reasons for hyperkalemia are chronic kidney disease and application of drugs that inhibit the renin–angiotensin–aldosterone system (RAAS) – e.g. ACE inhibitors, angiotensin II receptor antagonists, or potassium-sparing diuretics – or that interfere with kidney function in general, such as nonsteroidal anti-inflammatory drugs (NSAIDs).

Adverse effects

Patiromer was generally well tolerated in studies. Side effects that occurred in more than 2% of patients included in clinical trials were mainly gastro-intestinal problems such as constipation, diarrhea, nausea, and flatulence, and also hypomagnesemia (low levels of magnesium in the blood) in 5% of patients, because patiromer binds magnesium in the gut as well.

Interactions

Patiromer was tested for drug-drug interactions with 28 drugs and showed binding or interaction with 14 of these drugs. This could reduce their availability and thus effectiveness, wherefore patiromer has received a boxed warning by the US Food and Drug Administration (FDA), telling patients to wait for at least six hours between taking patiromer and any other oral drugs.

Of the 14 drugs that did show an interaction in vitro, 12 were selected for further testing in phase 1 studies in healthy volunteers to assess whether the results seen in vitro translated into an effect in people. These studies showed patiromer did not alter the absorption of nine of the 12 drugs when co-administered. Patiromer reduced absorption of three drugs when co-administered, however, there was no interaction when patiromer and these three drugs were taken 3 hours apart.

This information was submitted to the FDA in the form of a supplemental New Drug Application (sNDA) and as a result, in November 2016 the FDA approved the removal of the boxed warning regarding the separation of patiromer and other oral medications. The updated label recommends patients take patiromer at least three hours before or three hours after other oral medications.

Pharmacology

Mechanism of action

Patiromer works by binding free potassium ions in the gastrointestinal tract and releasing calcium ions for exchange, thus lowering the amount of potassium available for absorption into the bloodstream and increasing the amount that is excreted via the feces. The net effect is a reduction of potassium levels in the blood serum.

Lowering of potassium levels is detectable seven hours after administration. Levels continue to decrease for at least 48 hours if treatment is continued, and remain stable for 24 hours after administration of the last dose. After this, potassium levels start to rise again over a period of at least four days.

Pharmacokinetics

Patiromer is not absorbed from the gut, is not metabolized, and is excreted in unchanged form with the feces.

Chemistry

The substance is a cross-linked polymer of 2-fluoroacrylic acid with divinylbenzenes and 1,7-octadiene. It is used in form of its calcium salt (ratio 2:1) and with sorbitol (one molecule per two calcium ions or four fluoroacrylic acid units), a combination called patiromer sorbitex calcium.

Patiromer sorbitex calcium is an off-white to light brown, amorphous, free-flowing powder. It is insoluble in water, 0.1 M hydrochloric acid, heptane, and methanol.

History

In a Phase III multicenter clinical trial including 237 patients with hyperkalemia under RAAS inhibitor treatment, 76% of participants reached normal serum potassium levels within four weeks. After subsequent randomization of 107 responders into a group receiving continued patiromer treatment and a placebo group, re-occurrence of hyperkalemia was 15% versus 60%, respectively.

Society and culture

Legal status

The US FDA approved patiromer in October 2015. It was approved for use in the European Union in July 2017.[6]

Notes and References

  1. Web site: Prescription medicines: registration of new chemical entities in Australia, 2017 . Therapeutic Goods Administration (TGA) . 21 June 2022 . 9 April 2023.
  2. Web site: Prescription medicines and biologicals: TGA annual summary 2017 . Therapeutic Goods Administration (TGA) . 21 June 2022 . 31 March 2024.
  3. Web site: Summary Basis of Decision (SBD) for Veltassa . . 23 October 2014 . 29 May 2022 . 31 May 2022 . https://web.archive.org/web/20220531065149/https://hpr-rps.hres.ca/reg-content/summary-basis-decision-detailTwo.php?linkID=SBD00418&lang=en . live .
  4. Web site: Patiromer Sorbitex Calcium Monograph for Professionals . Drugs.com . 13 November 2019 . February 2017 . 13 November 2019 . https://web.archive.org/web/20191113062153/https://www.drugs.com/monograph/patiromer-sorbitex-calcium.html . live .
  5. Web site: Veltassa (Patiromer) Powder for Oral Suspension . U.S. Food and Drug Administration (FDA) . 25 November 2015 . 24 February 2023 . 4 May 2022 . https://web.archive.org/web/20220504130422/https://www.accessdata.fda.gov/drugsatfda_docs/nda/2015/205739Orig1s000TOC.cfm . live .
  6. Web site: Veltassa EPAR . European Medicines Agency (EMA) . 17 September 2018 . 18 October 2020 . 21 October 2020 . https://web.archive.org/web/20201021163527/https://www.ema.europa.eu/en/medicines/human/EPAR/veltassa . live .