Safety and efficacy of pegfilgastim for the prophylaxis of chemotherapy-induced neutropenia: A prospective, observational, multicenter, single-arm study

When the body fights cancer, the weapons used are often powerful drugs that destroy fast-growing cells. Unfortunately, these drugs cannot always distinguish between a cancer cell and the healthy cells that build our immune system. One of the most critical healthy cells to lose is the neutrophil, a type of white blood cell that acts as the body's first line of defense against infection. When a patient's neutrophil count drops too low, a condition known as neutropenia, even a minor infection can become life-threatening. If a fever develops during this vulnerable window, it becomes a medical emergency called febrile neutropenia, often requiring hospitalization, strong antibiotics, and a pause in the cancer treatment. To prevent this dangerous drop in white blood cells, doctors use a helper drug called pegfilgrastim. This substance is a long-acting version of a natural protein that tells the bone marrow to produce more neutrophils quickly. While the medicine itself is well-known, the way patients receive it has evolved. Instead of visiting a clinic for a nurse to give an injection, many patients now use a pre-filled device that allows them to give the shot themselves at home.

A team of researchers in Romania set out to see how this self-injection method worked in the real world, outside the strict walls of a controlled clinical trial. They followed 387 adult patients with various types of cancer, including breast cancer, lymphoma, and lung cancer, who were receiving chemotherapy that carried a high risk of dropping their white blood cell counts. Over a period of several months, these patients received their chemotherapy and then used a specific brand of pegfilgrastim self-injector to protect themselves. The researchers did not compare this group to another group of patients; instead, they simply watched and recorded what happened to these 387 individuals as they went through their treatment cycles. Their goal was to determine if this convenient method of delivery was safe, if it caused pain or other problems, and if it successfully kept the patients healthy enough to continue their cancer therapy without interruption.

The study found that the self-injector was generally safe and well-tolerated by a diverse group of people. Out of the 387 patients who started the treatment, nearly all of them received at least one dose, and the vast majority completed the planned course of treatment. While some patients experienced side effects, they were mostly mild. The most common issues were reactions at the spot where the needle went in, such as redness or soreness, and aches in the bones or muscles. About one-third of the patients reported at least one of these minor side effects, but serious problems were rare. Only a small number of patients had to stop using the device because of how they felt, and only one serious event was linked directly to the drug itself. Tragically, one patient passed away during the study, but the doctors determined that this was due to the patient's advanced cancer and other heart conditions, not the injection. The most worrying complication, febrile neutropenia, happened in only a tiny fraction of the group, suggesting the drug did its job of keeping the immune system strong.

Beyond safety, the researchers looked at how easy the patients found it to use the device on their own. At the beginning of the study, about three-quarters of the patients felt comfortable giving themselves the shot. By the end of the treatment period, that number had risen to nearly nine out of ten. When asked to rate the experience, most patients described the device as very easy to handle, with the vast majority saying it was simple to use. The pain from the injection itself was usually very low, and the bone or muscle aches that sometimes follow this type of treatment were also mild for most people. The study also tracked whether the patients had to delay their chemotherapy or take lower doses because of side effects. While some delays and dose reductions did occur, the researchers noted that these were likely due to the severity of the patients' cancer or other health factors rather than problems with the injection method. The data showed that the self-injector did not cause the treatment to be interrupted more often than expected.

This large observation of everyday medical practice suggests that letting patients administer their own protective injections at home is a practical and safe option. The results indicate that the device works well for a wide range of people, from younger adults to those in their eighties, and for different types of cancer. The low rate of severe infections and the high level of patient comfort with the device support the idea that this method can help keep cancer treatment on track. By allowing patients to stay in their own homes rather than visiting clinics for every dose, this approach offers a way to manage a serious risk without adding to the burden of hospital visits. The study confirms that for the patients involved, the self-injector was a reliable tool that helped them navigate the difficult path of chemotherapy with fewer interruptions and a manageable level of discomfort.