Question: Which receptor is targeted by telcagepant?

Context:
In vivo quantification of calcitonin gene-related peptide receptor occupancy by telcagepant in rhesus monkey and human brain using the positron emission tomography tracer [11C]MK-4232.
Lack of hemodynamic interaction between CGRP-receptor antagonist telcagepant (MK-0974) and sumatriptan: results from a randomized study in patients with migraine.
Olcegepant is the first selective CGRP receptor antagonist of proven efficacy in migraine. Olcegepant could only be administered intravenously and never taken beyond Phase II. Telcagepant is orally available and several completed Phase III trials have revealed positive results. 
Telcagepant (MK-0974) is a novel calcitonin gene-related peptide (CGRP) receptor antagonist currently undergoing clinical trials for migraine (http://www.merck.com/research/pipeline/home.html).
Four chemically unrelated CGRP receptor (CGRP-R) antagonists (olcegepant, telcagepant, MK-3207 and BI 44370 TA) have displayed efficacy in the treatment of migraine. 
Telcagepant is a calcitonin gene-related peptide (CGRP) receptor antagonist being evaluated for acute migraine treatment. 
BACKGROUND: Calcitonin gene-related peptide receptor antagonists, such as telcagepant, may be useful for acute migraine treatment in patients with cardiovascular disease, a population for whom triptans are contraindicated.
The calcitonin gene-related peptide (CGRP) receptor antagonists (gepants)-olcegepant (BIBN 4096 BS), telcagepant (MK-0974), MK3207, and BI 44370 TA-are effective in treating acute migraine. 
Telcagepant, a calcitonin gene-related peptide receptor antagonist, is being developed for the acute treatment of migraine. 
The potent calcitonin gene-related peptide receptor antagonist, telcagepant, does not affect nitroglycerin-induced vasodilation in healthy men.
AIMS: To assess the effect of the calcitonin gene-related peptide (CGRP) receptor antagonist, telcagepant, on the haemodynamic response to sublingual nitroglycerin (NTG). 
BACKGROUND: Telcagepant is an oral calcitonin gene-related peptide receptor antagonist which is being evaluated for the acute treatment of migraine. 
BACKGROUND: The calcitonin gene-related peptide (CGRP) receptor antagonists olcegepant and telcagepant are very potent drugs. 
CONCLUSION: The apparently high doses of CGRP receptor antagonists, olcegepant and telcagepant needed for anti-migraine effect are not so high after all. 
Dose-response curves for headaches relief and adverse events (AEs) are presented for five triptans: sumatriptan, zolmitriptan, naratriptan, almotriptan, and frovatriptan, and the CGRP antagonist telcagepant.
INTRODUCTION: Telcagepant (MK-0974) is a novel, orally active and selective CGRP receptor antagonist being investigated for acute treatment of migraine.
Calcitonin gene-related peptide (CGRP) receptor antagonists are another promising nonvasoconstrictor approach to treating acute migraine. Olcegepant (BIBN4096BS) and telcagepant (MK-0974) have been shown to be safe and effective in phase I, II, and (for telcagepant) phase III clinical trials. 
Background.- Telcagepant is a calcitonin gene-related peptide (CGRP) receptor antagonist being investigated for the acute treatment of migraine.
In 3 randomized clinical trials (n = 1585) the calcitonin gene-related peptide antagonist telcagepant 300 mg orally had an incidence of adverse events similar to placebo when used in the acute treatment of migraine. 
BACKGROUND: Telcagepant is an oral calcitonin gene-related peptide receptor antagonist with acute antimigraine efficacy comparable to oral triptans
METHODS: This study evaluated the calcitonin gene-related peptide (CGRP) receptor antagonist telcagepant (tablet formulation) for treatment of a migraine attack and across four attacks.
A highly efficient, asymmetric synthesis of telcagepant (1), a CGRP receptor antagonist for the treatment of migraine, is described
Asymmetric synthesis of telcagepant, a CGRP receptor antagonist for the treatment of migraine.
Sustained pain freedom and no adverse events as an endpoint in clinical trials of acute migraine treatments: application to patient-level data from a trial of the CGRP receptor antagonist, telcagepant, and zolmitriptan.
METHODS: The aim of this study was to evaluate new composite efficacy-plus-tolerability endpoints based on a post-hoc analysis of patient-level data from a previous randomized, placebo-controlled trial of the calcitonin gene-related peptide (CGRP) receptor antagonist, telcagepant, and zolmitriptan in the acute treatment of migraine.
Effect of the calcitonin gene-related peptide (CGRP) receptor antagonist telcagepant in human cranial arteries.
MATERIALS AND METHODS: We investigated the effect of the CGRP receptor antagonist, telcagepant, on CGRP-induced cranial vasodilatation in human isolated cerebral and middle meningeal arteries. 
CONCLUSIONS: Our findings provide morphological and functional data on the presence of CGRP receptors in cerebral and meningeal arteries, which illustrates a possible site of action of telcagepant in the treatment of migraine.
Characterization of the calcitonin gene-related peptide receptor antagonist telcagepant (MK-0974) in human isolated coronary arteries.
We therefore investigated the effects of the antimigraine CGRP receptor antagonist telcagepant (MK-0974) [N-[(3R,6S)-6-(2,3-difluorophenyl)-2-oxo-1-(2,2,2-trifluoroethyl)azepan-3-yl]-4-(2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridine-1-yl)piperidine-1-carboxamide] on human isolated coronary arteries. 
These findings in vitro support the cardiovascular safety of CGRP receptor antagonists and suggest that telcagepant is unlikely to induce coronary side effects under normal cardiovascular conditions.
Towards this end, the non-peptide CGRP receptor antagonists olcegepant and telcagepant have been shown to be effective in the acute treatment of migraine. While telcagepant is being pursued as a frontline abortive migraine drug in a phase III clinical trial, an oral formulation of a novel CGRP receptor antagonist, BI 44370, is currently in phase II clinical trials.
Telcagepant represents a new class of antimigraine drug-the calcitonin gene-related peptide receptor blockers. 
The CGRP receptor antagonists telcagepant and olcegepant (BIBN4096BS) have demonstrated clinical efficacy in the treatment of migraine and there is now a need to better understand how these molecules interact with the receptor. 
Single- and multiple-dose pharmacokinetics and tolerability of telcagepant, an oral calcitonin gene-related peptide receptor antagonist, in adults.
Telcagepant is a novel, orally active, and selective calcitonin gene-related peptide receptor antagonist being developed for acute treatment of migraine with and without aura. 
Studies were conducted in human isolated coronary arteries to explore the vascular effects of the calcitonin gene-related peptide (CGRP) receptor antagonist telcagepant and to compare its coronary vasoconstrictive potential to that of zolmitriptan. 
Intravenous BIBN4096BS (olcegepant) and oral MK-0974 (telcagepant), two CGRP-receptor antagonists, were safe and effective in the treatment of migraine attacks in Phase I and II trials. 
Telcagepant (MK-0974) is a novel oral calcitonin gene-related peptide (CGRP) receptor antagonist and is currently under clinical development.

Answer: Telcagepant (MK-0974) is a novel calcitonin gene-related peptide (CGRP) receptor antagonist currently undergoing clinical trials for migraine.
Exact answer: calcitonin gene-related peptide