Telotristat Ethyl is an extremely significant introduction to the treatment of Carcinoid Syndrome diarrhea. It’s the first addition to the standard of care in more than 16 years and the first time an oral syndrome treatment has been developed. The drug was previously known as Telotristat Etiprate but was changed to Ethyl in Oct 2016. ‘Etiprate’ was previously a truncation of ‘ethyl hippurate’. The brand name is XERMELO®
Who is the drug for?
The drug may be of benefit to those whose carcinoid syndrome diarrhea is not adequately controlled by somatostatin analogues (Octreotide/Lanreotide). It doesn’t replace somatostatin analogues – it is an additional treatment alongside.
The US FDA approved the drug 28 February 2017. On 21 July 2017, the scientific committee of the EMA (known as Committee for Medicinal Products for Human Use (CHMP)) has adopted a positive opinion recommending the approval of Xermelo® (telotristat ethyl) 250 mg three times a day for the treatment of carcinoid syndrome diarrhea in combination with somatostatin analogue (SSA) therapy in adults inadequately controlled by SSA therapy. The CHMP positive opinion will now be reviewed by the European Commission (EC), which has the authority to approve medicines for use in the 28 countries of the European Union, as well as Norway, Liechtenstein and Iceland. The detailed recommendations for the use of this product will be described in the Summary of Product Characteristics (SmPC), to be made available once the medication receives marketing authorization from the European Commission. The Ipsen press release is here.
In addition to the European submission, Ipsen will pursue a worldwide regulatory plan for marketing authorisation submissions in the territories in which it operates. Once approved, Ipsen will be distributing the drug in all countries less USA and Japan where Lexicon retains the rights. The approval estimate outside USA is not yet clear but my best guess is that the EU approval should be later in 2017 and then subject to local regulations for access to treatment and reimbursement. Outside USA and Europe will be constrained by national approval timelines.
How does it work?
In the simplest of terms, the drug is an inhibitor of the enzyme tryptophan hydroxylase (TPH). TPH is the rate-limiting enzyme in serotonin synthesis which converts tryptophan (an essential amino acid which comes from diet) to 5-hydroxytryptophan, which is subsequently converted to serotonin, one of the main causes of carcinoid syndrome effects including carcinoid heart disease. The trial data indicates that Telotristat ethyl significantly reduced the frequency of bowel movements. Furthermore, it was also associated with “significantly reduced levels of urinary 5-HIAA“, a marker for systemic serotonin levels, which are typically elevated in severe carcinoid syndrome.
Resources for your perusal:
- You can read more about the trial data in a summary by Dr Matthew Kulke (Dana Farber) by CLICKING HERE (latest review from 2017 ASCO).
- There is also an excellent summary in video form by Dr Lowell Anthony (University of Kentucky) by CLICKING HERE. (“any reduction in diarrhea is meaningful“).
- The 2016 ENETS conference also indicated a knock on effect of reducing the risk of, and perhaps even halting Carcinoid Heart Disease. You can read about this by CLICKING HERE.
- An excellent technical description of the drug can be found by CLICKING HERE.
- The detailed output from the trial (results) can be found by CLICKING HERE.
- Great 2016 article from ASCO (American Society of Clinical Oncologists) can be found by CLICKING HERE.
- FDA Approval. CLICK HERE
- Lex Pharma press release on approval. CLICK HERE
- The manufacturer Lex Pharma have established a dedicated site – click here
I know some patients who participated in the trial and they seem to be positive about the drug – if anyone can make a comment, that might be helpful to others who are thinking
Thanks for reading