100 Migraine Drugs, A to Z: galcanezumab
Galcanezumab (Emgality) was the third drug in the family of CGRP monoclonal antibodies (mAbs) to become approved by the FDA for the prevention of migraines. It is more similar to fremanezumab (Ajovy) in its mechanism of action than to erenumab (Aimovig). Erenumab is an antibody that blocks the CGRP receptor, while galcanezumab and fremanezumab are antibodies that block the CGRP molecule. This may explain the fact that some patients who do not respond to one of these drugs may respond to another. Actually, even patients who do not respond or respond only partially to fremanezumab may respond to galcanezumab and the other way around. This should not be surprising since many drugs with the same mechanism of action may have different efficacy and side effects in different patients. In migraine treatment this applies to triptans, such as sumatriptan (Imitrex), rizatriptan (Maxalt), eletriptan (Relpax), and other, as well as beta blockers, such as propranolol (Inderal), atenolol (Tenormin), nebivolol (Bystolic).
Just like the other two CGRP mAbs, galcanezumab is injected monthly (although fremanezumab can be also given at a triple dose every three months). The initial dose is 240 mg, or two auto-injector pens, followed by a monthly dose of 120 mg. The main side effects are similar to the other two drugs, namely injection site reactions such as swelling, redness, and an allergic rash. Erenumab can be constipating, while the other two drugs are much less so.
The cost of all 3 drugs is the same – between $550 and $600 per monthly injection, but most insurers will pay for them if certain conditions are met. The main condition is that the patient first try and fail two oral preventive medications such as beta blockers listed above, an antidepressant such as amitriptyline (Elavil), nortriptyline (Pamelor), or duloxetine (Cymbalta), or an epilepsy drug such as topiramate (Topamax) or divalproex sodium (Depakote).
Another, more recent requirement from many insurers, is that the patient not be receiving Botox. This prohibition is very upsetting because it is not based on any science and because many patients find that together these treatments (Botox and a CGRP mAb) provide almost complete relief of their migraine attacks. Both Botox and CGRP mAbs can be life-changing on their own with dramatic relief in about 20% of patients, while another 50% of patients obtain only partial relief. This is a very rational combination because these treatments work in a totally different way and both are extremely safe with no drug interactions. The insurers justify their refusal by the fact that there are no published studies showing the safety of this combination, which is ludicrous. Some insurers, such as Cigna, go a step further in their obnoxiousness – even if a patient gets free mAb from the manufacturer or pays out of pocket, they refuse to pay for Botox. How do they know if the patient is getting a mAb? – to get prior approval for Botox we have to submit our medical notes.
All three manufacturers of mAbs, Amgen, Teva, and Eli Lilly provide up to one year of free medicine if your commercial insurance refuses to pay for it. Check each manufacturer’s website – Aimovig.com, Ajovy.com, and Emgality.com. Allergan, Botox manufacturer offers up to $700 off each quarterly treatment, so if you are paying out-of-pocket or have a high copay or deductible, check BotoxSavingsProgram.com
No, I have no objections to combining Emgality with sumatriptan. I prescribe this combination to many patients.
Dr Mauskop, after my original Emgality injections Feb 22, 2021, which produced a ‘hormonal affect’, my gyn checked me out, reduced my Estradiol patch dosage by half and gave me a clean Bill of health. By that time, the Emgality began to wear off and despite having continued my nightly sumatriptan preventive, the migraine came back and hit me like a ton of bricks. I have since received another double loading dose of Emgality and a prescription for it and I am still taking a nightly preventive sumatriptan, but my supply of sumatriptan could run out before my next doctor appointment.
The Emgality brochure states that it has been found to reduce migraine by half in some participants. That means I likely will have 15 migraines a month WITHOUT the combination of sumatriptan and Emgality.
I am elderly and sick and I am very scared of flying to New York City and frightened at the thought of attempting to navigate from the airport to your office.
I have printed the documents to begin a telemedicine visit. Before I begin that process, are you opposed – in general principle – to a combination of sumatriptan and Emgality?
I had a calcium score test last year which showed I had a score of five.
I don’t have too many years left. I would prefer that those years not be spent suffering migraine pain and malaise in bed.
Thank you, Dr Mauskop, for replying. I very much appreciate your caring and compassion.
I will report to the FDA.
Yes, a few of my patients also had a hormonal effect from CGRP monoclonal antibodies. Patients also reported to me and my colleagues a wide variety of side effects. Clinical trials never reveal all potential side effects of new drugs. This is because the number of patients is relatively small (although at least 10,000 patients were enrolled in all CGRP trials), the patients who enroll tend to be younger and healthier, and because doctors conducting the trials do not consider unexpected and infrequent side effects to be caused by the drug.
There is no way to get information from the drug companies about side effects reported to them by patients. However, if enough people report them to the companies or the FDA, the label is updated. This happened with Aimovig. Its label now includes the risk of severe constipation and hypertension, which was not mentioned initially. So please report your experience to the company or to the FDA.
Dr Mauskop, I received a double loading dose of Emgality on February 24, 2021. Despite being 65 years old, the following day on February 25. 2021 I began a bleeding menstrual cycle, I would describe as “flooding”. I called my gyn, was told to peel off the estradiol patch, and within a couple of days. I had an ultrasound and a biopsy of the cervix, which thankfully was negative. I began a search in the medical “literature” for any connection and found none.
But, I did find this “forum”:
https://www.reddit.com/r/cgrpMigraine/comments/cws60d/can_emgality_trigger_your_period/
If the Emgality provided any improvement, it was quickly upended by the dramatic hormonal swings of removing a 0.1 mg estradiol patch and the withdrawal of that steady release of estradiol.
Needless to say, I will not have another Emgality injection.
There is no doubt in my mind that the Emgality injection is the direct and primary cause of the vaginal bleeding the day after.
There is also no doubt in my mind that the forum I linked wherein much younger women reported abnormal menstrual periods, two periods a month, periods despite using birth control whereby they should not experience bleeding is based on experience of FACT.
The first question which springs to my mind is: how, during the course of clinical trials, this was not connected and reported as a side effect?
I understand you did not conduct these clinical trials, but I am interested if you have had reports from your patients of post-menopausal menstrual cycles the day following injection.
Also, if you have a pipeline to the manufacturers, perhaps you can ask them to disclose links to their drug and abnormal menstrual periods.
The only benefit suggested by the double loading dose of Emgality before the heavy bleeding distracted me was – perhaps – less sensitivity to bright sunshine, and that only for a day as I was then consumed by setting up appointments for medical procedures. I always wear an oversized visor and prescription sunglasses outside.
Fortunately, the Emgality should be out of my system within a month of the injection.
Any insight you can shed is welcome.
L. White
Dear Dr. Mauskop,
In addition to having chronic migraine, I have IBS-C and I’ve had repeated attacks this past month since starting Emgality, so not going to continue with it. My GI doctor always advises daily Citrucel which works (he says I can also use miralax, but the citrucel fiber is key). I use the regular Citrucel (not the sugar free) but it does list “natural flavors” on its ingredient list. I think we discussed this before, but I’m in a balancing act again – is it likely that Citrucel is a migraine trigger? I can talk to him about an alternative if so – like GG crackers. Hoping the IBS gets better as the Emgality leaves my system – so glad you only gave me a half loading dose!
Thank you so much.
Thank you for this post about Emgality. I tried Aimovig for four months and had very good results (50 percent reduction in headache frequency). However, I developed tinnitus at the same time, so my doctor just switched me to Emgality, just in case the Aimovig was the cause. I hope I see the same or better efficacy with Emgality. I also discontinued Botox, but I may need to restart that at some point. I’m frustrated that both treatments (CGRP and Botox) are not covered by insurance. Surely this will change as many patients discover that they need both treatments to be fully functional. The reduction in triptan costs alone will be beneficial to many insurers! Thank you for keeping the migraine community well informed with this helpful blog.