Clicking moves left

Enhanced Elimination in Toxicology

Enhanced Elimination in Toxicology Extracorporeal eliminationExtracorpore [...]

Decontamination in Toxicology

Decontamination in ToxicologyorHow to Decontamination in ToxicologySingle-dose [...]

Resuscitation in Toxicology

Resuscitation in ToxicologySupportive careInitial resuscitation should be based [...]

Key investigations of Toxicology

Key investigations of Toxicology In this topic: Electrocardiography Drug conce [...]

Arterial blood gases in Toxicology

Arterial blood gases in Toxicology Arterial blood gases are an important in [...]

Clicking moves right
M O V I E
TRAVELING

Pharmacology of Disopyramide Indication For the treatment of documented ventricular arrhythmias, such as [...]

Pharmacology of Ranolazine Indication For the treatment of chronic angina. It should be used in combinati [...]

Pharmacology of Milrinone Indication Indicated for the treatment of congestive heart failure. Pharma [...]

Pharmacology of Midodrine   Indication For the treatment of symptomatic orthostatic hypotension [...]

Pharmacology of Dofetilide  Indication For the maintenance of normal sinus rhythm (delay in time to [...]

GALLERY

Anxiety disorders may be classified asgeneralized anxiety disorder, panic disorder, obsessive-compu [...]

Post-Traumatic Stress DisorderPost-traumatic stress disorder develops following a traumatic event that elicit [...]

Social Anxiety DisorderSocial anxiety disorder, formerly known as social phobia, is characterized by an inten [...]

TOP LINE

Anxiety disorders may be classified asgeneralized anxiety disorder, panic disorder, obsessive-compulsive disorder, social anxiety disorder, post-traumatic stress disorder. Click to view each type....

REVIEW

Hormonal contraceptivesHormonal contraceptives inhibit ovulation. Contraceptives typically contain a combination of hormones. Fo...

Erectile dysfunction therapy drugsErectile dysfunction therapy drugs treat penile erectile dysfunction that results from a lack ...

Urinary tract antispasmodicsUrinary tract antispasmodics help decrease urinary tract muscle spasms. They include darifenacin, fl...

ANALYSIS

Pharmacology of Disopyramide Indication For the treatment of documented ventricular arrhythmias, such as sustained ventricul...

Pharmacology of Ranolazine Indication For the treatment of chronic angina. It should be used in combination with amlodipine, ...

Pharmacology of Milrinone Indication Indicated for the treatment of congestive heart failure. Pharmacodynamics Milri...

HIGHLIGHT
[ more from label ]
Classification of Anxiety Disorders
Post-Traumatic Stress Disorder
Social Anxiety Disorder
Obsessive-Compulsive Disorder
Latest News Updates
PERFORMANCE

Pharmacology of Disopyramide Indication For the treatment of documented ventricular arrhythmias, such as ...

FEATURE

Anxiety disorders may be classified asgeneralized anxiety disorder, panic disorder, obsessive-compu...

Targeted therapies
Thursday, July 21, 2011 Posted by Piscean


Targeted therapies
A groundbreaking approach to anticancer therapies involves targeting proteins associated with the growth patterns of specific types of cancer. Drugs used for this new approach to cancer treatment include:
  • bortezomib
  • gefitinib
  • imatinib.
Pharmacokinetics
Bortezomib isn’t absorbed orally and must be given I.V. It’s extensively distributed into body tissues and metabolized by the liver.
Gefitinib is available in an oral form, and about half of the dose is absorbed. The drug is widely distributed in tissues. It undergoes hepatic metabolism with minimal urinary excretion.
Imatinib is also available in an oral form and is almost completely absorbed. It’s 95% bound to plasma proteins and is extensively metabolized by the liver. The half-life of imatinib is about 15 hours.
Pharmacodynamics
Bortezomib inhibits proteosomes, which are involved in integral cell-cycle function and promote tumor growth. Proteolysis by bortezomib results in disruption of the normal homeostatic mechanisms and leads to cell death.

Too much of this…
Gefitinib inhibits the epidermal growth factor receptor-1 tyrosine kinase, which is overexpressed in such cancers as non’small-cell lung cancer. This inhibition blocks signaling pathways for growth, survival, and metastasis of cancer.

…too many of those
In patients with chronic myeloid leukemia, the BCR-ABL protein stimulates other tyrosine kinase proteins, causing an abnormally high production of WBCs. Imatinib binds to the adenosine triphosphate’binding domain of the BCR-ABL protein, effectively shutting down the abnormal WBC production.
Pharmacotherapeutics
Bortezomib is used to treat multiple myeloma that has relapsed after standard chemotherapy.
Gefitinib is used as a single agent for patients with non’small-cell lung cancer that hasn’t responded to two standard chemotherapy regimens.
Imatinib is used to treat chronic myeloid leukemia, acute lymphoid leukemia, and GI stomal tumors.
Drug interactions
Bortezomib, gefitinib, and imatinib have been associated with some drug interactions.
  • Bortezomib when taken with drugs that inhibit cytochrome CYP3A4 (such as amiodarone, cimetidine, erythromycin, diltiazem, fluoxetine, verapamil, zafirlukast, and zileuton) or induce cytochrome CYP3A4 (such as amiodarone, carbamazepine, nevirapine, phenobarbital, phenytoin, and rifampin), could cause either toxicities or reduced efficacy of these drugs.
  • Bortezomib when taken with oral hypoglycemics could cause hypoglycemia and hyperglycemia in patients with diabetes.
  • Plasma levels of gefitinib and imatinib are reduced, sometimes substantially, when these drugs are given with carbamazepine, dexamethasone, phenobarbital, phenytoin, rifampin, or St. John’s wort.
  • High doses of ranitidine with sodium bicarbonate when taken with gefitinib reduce gefitinib levels.
  • Administration of gefitinib or imatinib with warfarin causes elevations in the International Normalized Ratio, increasing the risk of bleeding.
  • Clarithromycin, erythromycin, itraconazole, and ketoconazole, when taken with imatinibor may increase imatinib plasma levels.
    P.402

  • Carbamazepine, dexamethasone, phenobarbital, phenytoin, or rifampin given with imatinib may increase metabolism of imatinib and decrease imatinib level.
  • Imatinib given with simvastatin increases simvastatin levels about threefold.
  • Imatinib increases plasma levels of other CYP3A4-metabolized drugs, such as triazolo-benzodiazepines, calcium channel blockers, and certain HMG-CoA reductase inhibitors. 
Unclassifiable antineoplastic drugs
Many other antineoplastic drugs can’t be included in existing classifications. These drugs include:
  • arsenic trioxide
  • asparaginases
  • procarbazine
  • hydroxyurea
  • interferon
  • aldesleukin
  • altretamine
  • paclitaxel (taxane)
  • docetaxel (taxane).

Piscean

Thanks for your visit..!

0 comments for "Targeted therapies"

Leave a reply